CI: update golang-release image ref

- remove unused task
- remove image_resource reference that is outdated

Author: aramprice

ci/pipelines/stemcells-windows.yml

@@ -204,9 +204,7 @@ resources:
 - name: golang-release-image
   type: registry-image
   source:
-    repository: bosh/golang-release
-    username: ((docker.username))
-    password: ((docker.password))
+    repository: ghcr.io/cloudfoundry/bosh/golang-release
 - name: bosh-integration-registry-image
   type: registry-image
   source:

ci/tasks/build-azstemcell/task.yml

@@ -1,9 +1,5 @@
 ---
 platform: linux
-image_resource:
-  type: registry-image
-  source:
-    repository: bosh/golang-release
 
 inputs:
 - name: bosh-windows-stemcell-builder-ci