Replace "-" with ":" to correctly utilize github sha as tag

Author: benkoppe

.github/workflows/ci-container.yml

@@ -13,7 +13,7 @@ jobs:
       push: ${{ github.event.pull_request.head.repo.full_name == github.repository }}
       tags: |
         ghcr.io/${{ github.repository }}/pr-${{ github.event.pull_request.number }}:latest
-        ghcr.io/${{ github.repository }}/pr-${{ github.event.pull_request.number }}-${{ github.sha }}
+        ghcr.io/${{ github.repository }}/pr-${{ github.event.pull_request.number }}:${{ github.sha }}
       labels: |
         org.opencontainers.image.source=${{ github.event.pull_request.html_url }}
         org.opencontainers.image.title=PR-${{ github.event.pull_request.number }}