github: build-container: Fix cached image loading

Before cached images meant that the e2e tests would fail.

Additionally, before changing go dependencies meant that the
image would not rebuild. Now if backend dependencies change
a new image is built and tested.

Signed-off-by: René Dudfield <[email protected]>

.github/workflows/build-container.yml

@@ -47,7 +47,7 @@ jobs:
       with:
         path: ~/image-cache
         # cache the container image. All the paths this PR depends on except the e2e-tests folder for the key.
-        key: ${{ runner.os }}-image-${{ hashFiles('backend/pkg/**', 'backend/cmd/**', 'frontend/src/**', 'frontend/package.json', 'frontend/package-lock.json', 'Makefile', '.github/**', 'Dockerfile', 'Dockerfile.plugins') }}
+        key: ${{ runner.os }}-image-${{ hashFiles('backend/pkg/**', 'backend/cmd/**', 'backend/go.*', 'frontend/src/**', 'frontend/package.json', 'frontend/package-lock.json', 'Makefile', '.github/workflows/build-container.yml', 'Dockerfile', 'Dockerfile.plugins') }}
     - name: Restore Cached Docker Images
       if: steps.cache-image-restore.outputs.cache-hit == 'true'
       run: |
@@ -81,7 +81,6 @@ jobs:
         echo -n "verifying images:"
         docker images
     - name: Import images to kind
-      if: steps.cache-image-restore.outputs.cache-hit != 'true'
       run: |
         export SHELL=/bin/bash
         kind load docker-image ghcr.io/headlamp-k8s/headlamp-plugins-test:latest --name test