fix: always set the git rev env var when building an app via git:sync

Closes #6827

plugins/git/internal-functions

@@ -235,10 +235,11 @@ cmd-git-sync() {
   if [[ "$SHOULD_BUILD" == "true" ]]; then
     if [[ -n "$GIT_REF" ]]; then
       GIT_REF="$(fn-git-cmd "$APP_ROOT" rev-parse "$GIT_REF")"
-      plugn trigger receive-app "$APP" "$GIT_REF"
     else
-      plugn trigger receive-app "$APP"
+      GIT_REF="$UPDATED_REF"
     fi
+
+    plugn trigger receive-app "$APP" "$GIT_REF"
     plugn trigger deploy-source-set "$APP" "git-sync" "${GIT_REMOTE}#${GIT_REF}"
   fi
 }

tests/unit/git_3.bats

@@ -181,6 +181,11 @@ teardown() {
   assert_success
   assert_output_contains "Application deployed"
 
+  run /bin/bash -c "dokku config:get $TEST_APP GIT_REV"
+  echo "output: $output"
+  echo "status: $status"
+  assert_output_exists
+
   run /bin/bash -c "cat /home/dokku/$TEST_APP/refs/heads/master"
   echo "output: $output"
   echo "status: $status"