fix: Add DEF_TAG_NAME to env in release-heat-rxt.yml to fix empty ima…

…geTag issue (#542)

.github/workflows/release-heat-rxt.yml

@@ -23,6 +23,7 @@ on:
 env:
   REGISTRY: ghcr.io
   IMAGE_NAME: ${{ github.repository }}
+  DEF_TAG_NAME: 2024.1-ubuntu_jammy
 
 # There is a single job in this workflow. It's configured to run on the latest available version of Ubuntu.
 jobs:
@@ -42,6 +43,10 @@ jobs:
           registry: ${{ env.REGISTRY }}
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
+      # ghcr only allows lowercase repository names
+      - name: lowercase repo name
+        run: |
+          echo "IMAGE_NAME=${GITHUB_REPOSITORY,,}" >>${GITHUB_ENV}
       # This step uses [docker/metadata-action](https://github.com/docker/metadata-action#about) to extract tags and labels that will be applied to the specified image. The `id` "meta" allows the output of this step to be referenced in a subsequent step. The `images` value provides the base name for the tags and labels.
       - name: Extract metadata (tags, labels) for Docker
         id: meta
@@ -60,8 +65,8 @@ jobs:
           file: Containerfiles/HeatRXT-Containerfile
           push: true
           tags: |
-            ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}/heat-rxt:${{ github.event.inputs.imageTag }}
-            ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}/heat-rxt:${{ github.event.inputs.imageTag }}-${{ env.MY_DATE }}
+            ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}/heat-rxt:${{ github.event.inputs.imageTag || env.DEF_TAG_NAME }}
+            ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}/heat-rxt:${{ github.event.inputs.imageTag || env.DEF_TAG_NAME }}-${{ env.MY_DATE }}
           labels: ${{ steps.meta.outputs.labels }}
           build-args: |
-            VERSION=${{ github.event.inputs.imageTag }}
+            VERSION=${{ github.event.inputs.imageTag || env.DEF_TAG_NAME }}