tests: run mvdan/shfmt on test runs

While I do not agree with _every_ style change, this will force Dokku to have consistent formatting across all shell scripts, which is arguably a Good Thing™.

The command used to reprocess everything is:

```shell
shfmt -l -bn -ci -i 2 -w .
```

plugins/plugin/commands

@@ -1,12 +1,13 @@
 #!/usr/bin/env bash
 [[ " help plugin:help " == *" $1 "* ]] || exit "$DOKKU_NOT_IMPLEMENTED_EXIT"
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 
 case "$1" in
   help | plugin:help)
-    help_content_func () {
+    help_content_func() {
       declare desc="return plugin plugin help content"
-      cat<<help_content
+      cat <<help_content
     plugin:list, Print active plugins
     plugin:install [--core|git-url [--committish tag|branch|commit|--name custom-plugin-name]], Optionally download git-url (with custom tag/committish) & run install trigger for active plugins (or only core ones)
     plugin:install-dependencies [--core], Run install-dependencies trigger for active plugins (or only core ones)
@@ -17,15 +18,15 @@ case "$1" in
 help_content
     }
 
-    if [[ $1 = "plugin:help" ]] ; then
-        echo -e 'Usage: dokku plugin[:COMMAND]'
-        echo ''
-        echo 'View installed plugins and manage community plugins.'
-        echo ''
-        echo 'Additional commands:'
-        help_content_func | sort | column -c2 -t -s,
+    if [[ $1 == "plugin:help" ]]; then
+      echo -e 'Usage: dokku plugin[:COMMAND]'
+      echo ''
+      echo 'View installed plugins and manage community plugins.'
+      echo ''
+      echo 'Additional commands:'
+      help_content_func | sort | column -c2 -t -s,
     else
-        help_content_func
+      help_content_func
     fi
     ;;
 
@@ -34,5 +35,3 @@ help_content
     ;;
 
 esac
-
-

plugins/plugin/functions

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
 
 disable_plugin() {
@@ -37,11 +38,13 @@ download_and_enable_plugin() {
       -)
         case "$OPTARG" in
           committish)
-            val="${!OPTIND}"; OPTIND=$(( OPTIND + 1 ))
+            val="${!OPTIND}"
+            OPTIND=$((OPTIND + 1))
             local PLUGIN_COMMITTISH="$val"
             ;;
           name)
-            val="${!OPTIND}"; OPTIND=$(( OPTIND + 1 ))
+            val="${!OPTIND}"
+            OPTIND=$((OPTIND + 1))
             local CUSTOM_NAME="$val"
             ;;
         esac
@@ -52,7 +55,7 @@ download_and_enable_plugin() {
   dokku_log_info1_quiet "Cloning plugin repo $PLUGIN_GIT_URL to $PLUGIN_AVAILABLE_PATH/$PLUGIN_NAME"
   download_plugin "$PLUGIN_GIT_URL" "$PLUGIN_NAME"
   enable_plugin "$PLUGIN_NAME"
-  if [[ -n "$PLUGIN_COMMITTISH" ]];then
+  if [[ -n "$PLUGIN_COMMITTISH" ]]; then
     update_plugin "$PLUGIN_NAME" "$PLUGIN_COMMITTISH"
   fi
 }

plugins/plugin/internal-functions

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
 
 plugin_list_cmd() {
@@ -14,5 +15,5 @@ plugin_prime_bash_completion() {
   declare desc="primes the bash-completion cache"
 
   dokku_log_info1_quiet "Priming bash-completion cache"
-  dokku --quiet help --all | awk '/^    /{ print $1 }' | sort > "/var/cache/dokku-completion"
+  dokku --quiet help --all | awk '/^    /{ print $1 }' | sort >"/var/cache/dokku-completion"
 }

plugins/plugin/subcommands/default

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/internal-functions"
 

plugins/plugin/subcommands/disable

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/internal-functions"

plugins/plugin/subcommands/enable

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/internal-functions"

plugins/plugin/subcommands/install

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/internal-functions"
@@ -12,7 +13,7 @@ plugin_install_cmd() {
       [[ "$#" -gt 2 ]] && dokku_log_info1_quiet "Cannot install additional core plugins, running core plugin install trigger"
       PLUGIN_PATH="$PLUGIN_CORE_PATH" plugn trigger install
       ;;
-    https:*|git*|ssh:*|*.tar.gz|*.tgz)
+    https:* | git* | ssh:* | *.tar.gz | *.tgz)
       shift
       download_and_enable_plugin "$@"
       plugn trigger install

plugins/plugin/subcommands/install-dependencies

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 
 plugin_install_dependencies_cmd() {
   declare desc="calls dependencies plugin trigger via command line"

plugins/plugin/subcommands/list

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_AVAILABLE_PATH/plugin/internal-functions"
 
 plugin_list_cmd "$@"

plugins/plugin/subcommands/uninstall

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/functions"
 source "$PLUGIN_AVAILABLE_PATH/plugin/internal-functions"

plugins/plugin/subcommands/update

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_AVAILABLE_PATH/plugin/internal-functions"
 
 plugin_update_cmd() {