FrontendService: Fix backend.dockerfile (#108195)

* FrontendService: Fix backend.dockerfile

* comments

* Fix backends rebuilding image instead of just restarting when assets change

* route /logout to grafana backend

* fix script in dockerfile

Dockerfile

@@ -69,7 +69,8 @@ COPY go.* ./
 COPY .bingo .bingo
 COPY .citools .citools
 
-# Include vendored dependencies
+# Copy go dependencies first
+# If updating this, please also update devenv/frontend-service/backend.dockerfile
 COPY pkg/util/xorm pkg/util/xorm
 COPY pkg/apiserver pkg/apiserver
 COPY pkg/apimachinery pkg/apimachinery