fix release build

.github/workflows/release.yaml

@@ -13,6 +13,10 @@ jobs:
     steps:
     - name: Set up QEMU
       uses: docker/setup-qemu-action@v1
+    - name: Get tag
+      id: tag
+      uses: dawidd6/action-get-tag@v1
+    - uses: docker/build-push-action@v2
     - name: Set up Docker Buildx
       uses: docker/setup-buildx-action@v1
     - name: Log into GitHub Container Registry
@@ -22,9 +26,8 @@ jobs:
       with:
         platforms: linux/amd64
         push: true
-        tags: ghcr.io/meeb/${{ env.IMAGE_NAME }}:${{ env.RELEASE_TAG }}
-        cache-from: type=registry,ref=ghcr.io/meeb/${{ env.IMAGE_NAME }}:${{ env.RELEASE_TAG }}
+        tags: ghcr.io/meeb/${{ env.IMAGE_NAME }}:${{ steps.tag.outputs.tag }}
+        cache-from: type=registry,ref=ghcr.io/meeb/${{ env.IMAGE_NAME }}:${{ steps.tag.outputs.tag }}
         cache-to: type=inline
         build-args: |
           IMAGE_NAME=${{ env.IMAGE_NAME }}
-          RELEASE_TAG=${{ github.event.release.tag_name }}