[CI] Remove the previously added docker build action

Turns out that getting the whole repo for just this file isn't very performant
I've instead moved it to https://github.com/e621ng/publish-to-ghcr and published it properly

.github/docker-build-and-push/action.yml

@@ -1,36 +0,0 @@
-# Not used here but in other repos
-name: Docker Build and Push
-description: Docker Build and Push
-
-runs:
-  using: composite
-  steps:
-    - name: Set up Docker Buildx
-      uses: docker/setup-buildx-action@v2
-
-    - name: Login to Github Container Registry
-      uses: docker/login-action@v2
-      with:
-        registry: ghcr.io
-        username: ${{ github.repository_owner }}
-        password: ${{ github.token }}
-
-    - name: Generate Docker tags
-      uses: docker/metadata-action@v4
-      id: metadata
-      with:
-        images: ghcr.io/${{ github.repository }}
-        tags: |
-          type=sha,format=long,prefix=
-        flavor: |
-          latest=true
-
-    - name: Build and push
-      uses: docker/build-push-action@v4
-      with:
-        push: true
-        tags: ${{ steps.metadata.outputs.tags }}
-        labels: ${{ steps.metadata.outputs.labels }}
-
-        cache-from: type=gha
-        cache-to: type=gha,mode=max