refactor: fix computation test and remove the app-specific hsts value

The default for an app is empty, meaning it will fallback to the global value (which defaults to true). This will allow users to properly override the global value, regardless of what it is.

tests/unit/nginx-vhosts_6.bats

@@ -119,8 +119,12 @@ teardown() {
 
   # disable hsts globally
   run /bin/bash -c "dokku nginx:set --global hsts false"
+  echo "output: $output"
+  echo "status: $status"
+  assert_success
+
   # check it is now not applied
-  run /bin/bash -c "dokku nginx:build-config $TEST_APP"
+  run /bin/bash -c "dokku proxy:build-config $TEST_APP"
   echo "output: $output"
   echo "status: $status"
   assert_success
@@ -128,17 +132,25 @@ teardown() {
 
   # apply on app
   run /bin/bash -c "dokku nginx:set $TEST_APP hsts true"
+  echo "output: $output"
+  echo "status: $status"
+  assert_success
+
   # check it is now applied
-  run /bin/bash -c "dokku nginx:build-config $TEST_APP"
+  run /bin/bash -c "dokku proxy:build-config $TEST_APP"
   echo "output: $output"
   echo "status: $status"
   assert_success
   assert_output_contains "Enabling HSTS" 1
 
-  # disable globally
+  # set global value to default
   run /bin/bash -c "dokku nginx:set --global hsts"
+  echo "output: $output"
+  echo "status: $status"
+  assert_success
+
   # check it is still applied
-  run /bin/bash -c "dokku nginx:build-config $TEST_APP"
+  run /bin/bash -c "dokku proxy:build-config $TEST_APP"
   echo "output: $output"
   echo "status: $status"
   assert_success