🐳 Add GH Action for Docker publish

.github/workflows/main.yml

@@ -0,0 +1,24 @@
+name: Publish to Docker Registry
+on:    
+  release:
+      types: [published]
+  push:
+    branches:
+      - master
+  schedule:
+    - cron: '0 2 * * 0' # Weekly on Sundays at 02:00
+jobs:
+  update:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: Get release version
+      id: get_version
+      run: echo ::set-env name=RELEASE_VERSION::$(echo ${GITHUB_REF:10})
+    - name: Publish to Registry
+      uses: elgohr/Publish-Docker-Github-Action@master
+      with:
+        name: openclimatefix/metoffice_ec2
+        username: ${{ secrets.DOCKER_USERNAME }}
+        password: ${{ secrets.DOCKER_PASSWORD }}
+        tags: "latest,${{ env.RELEASE_VERSION }}"