chore: remove ARM support

Building/testing for ARM does not happen often - the only runtime environment is Raspberry PI, which supports ARM64 - and complicates support for a ton of features. Aside from that, CI runs are much longer for ARM Dokku images, often reaching 15-20 minutes or just timing out completely.

Rather than support an architecture that doesn't have much usage by maintainers and has a lot of maintenance burden, we're removing the platform.

plugins/00_dokku-standard/subcommands/report

@@ -22,7 +22,7 @@ cmd-report() {
   dokku_log_info1 "docker daemon info: "
   "$DOCKER_BIN" -D system info | sed "s/^/       /"
   dokku_log_info1 "herokuish version: "
-  if [[ "$ARCHITECTURE" == "armhf" ]] || [[ "$ARCHITECTURE" == "arm64" ]]; then
+  if [[ "$ARCHITECTURE" == "arm64" ]]; then
     dokku_log_warn "herokuish not supported on $ARCHITECTURE architecture"
   elif verify_image "$DOKKU_IMAGE"; then
     "$DOCKER_BIN" container run $DOKKU_GLOBAL_RUN_ARGS --rm "$DOKKU_IMAGE" herokuish version | sed "s/^/       /"

plugins/builder-herokuish/builder-detect

@@ -10,10 +10,8 @@ trigger-builder-herokuish-builder-detect() {
   declare APP="$1" SOURCECODE_WORK_DIR="$2"
   local ARCHITECTURE="$(dpkg --print-architecture 2>/dev/null || true)"
 
-  if [[ "$ARCHITECTURE" == "armhf" ]] || [[ "$ARCHITECTURE" == "arm64" ]]; then
-    if [[ "$(fn-builder-herokuish-computed-allowed "$APP")" != "true" ]]; then
-      return
-    fi
+  if [[ "$ARCHITECTURE" == "arm64" ]] && [[ "$(fn-builder-herokuish-computed-allowed "$APP")" != "true" ]]; then
+    return
   fi
 
   if fn-has-buildpacks-file "$SOURCECODE_WORK_DIR"; then

plugins/builder-lambda/builder-detect

@@ -9,10 +9,6 @@ trigger-builder-lambda-builder-detect() {
   declare APP="$1" SOURCECODE_WORK_DIR="$2"
   local ARCHITECTURE="$(dpkg --print-architecture 2>/dev/null || true)"
 
-  if [[ "$ARCHITECTURE" == "armhf" ]]; then
-    return
-  fi
-
   if [[ -f "$SOURCECODE_WORK_DIR/lambda.yml" ]]; then
     echo "lambda"
     return

plugins/git/functions

@@ -57,10 +57,6 @@ git_trigger_build() {
         dokku_log_warn "Herokuish builder not supported on $ARCHITECTURE servers."
         dokku_log_warn "Switching to pack builder."
         BUILDER="pack"
-      elif [[ "$ARCHITECTURE" == "armhf" ]]; then
-        dokku_log_warn "Herokuish builder not supported on $ARCHITECTURE servers."
-        dokku_log_warn "Consider using a Dockerfile to build your app."
-        return 1
       fi
     fi
   fi