GHA: Set push branch to devel

Author: reet-

.github/workflows/mirageos.yml

@@ -39,7 +39,7 @@ jobs:
           context: .
           file: ./docker/Dockerfile.muen-mirageos
           platforms: linux/amd64
-          push: ${{ github.ref == 'refs/heads/devel-59e3fac208fc-bob' }}
+          push: ${{ github.ref == 'refs/heads/devel' }}
           cache-from: type=local,src=/tmp/.buildx-cache
           cache-to: type=local,dest=/tmp/.buildx-cache
           tags: |