Push Docker image on workflow dispatch

Author: marip8

.github/workflows/docker.yml

@@ -25,7 +25,7 @@ jobs:
     env:
       REGISTRY: ghcr.io
       IMAGE_NAME: ${{ github.repository }}
-      PUSH_DOCKER_IMAGE: ${{ github.ref == 'refs/heads/master' || github.event_name == 'release' }}
+      PUSH_DOCKER_IMAGE: ${{ github.ref == 'refs/heads/master' || github.event_name == 'release' || github.event_name == 'workflow_dispatch' }}
     permissions:
       contents: read
       packages: write