Add Docker Hub description workflow

.github/workflows/dockerhub-readme.yml

@@ -0,0 +1,21 @@
+name: Docker Hub description
+on:
+  push:
+    branches: [master]
+    paths:
+      - docker/README.md
+      - .github/workflows/dockerhub-readme.yml
+jobs:
+  dockerHubDescription:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2.3.4
+      - name: Docker Hub Description
+        uses: peter-evans/dockerhub-description@v2.4.3
+        with:
+          username: 2fauth
+          password: ${{ secrets.DOCKERHUB_PASSWORD }}
+          repository: 2fauth/2fauth
+          short-description: A web app to manage your Two-Factor Authentication (2FA) accounts and generate their security codes
+          readme-filepath: docker/README.md