Add workflow for docker release (#82)

* add gh release workflow

.github/workflows/main.yml

@@ -1,6 +1,6 @@
-name: Docker CI
+name: Docker Test Build
 
-on: [push, pull_request]
+on: [pull_request]
 
 jobs:
   apiary-docker-image:

.github/workflows/release.yml

@@ -0,0 +1,44 @@
+name: Docker Release
+
+on:
+  push:
+    tags: 
+      - v* 
+
+jobs:
+  apiary-docker-image:
+    name: Apiary Docker Release
+    runs-on: ubuntu-18.04
+    steps:
+    - name: Check out code  
+      uses: actions/checkout@v2
+
+    - name: Release Apiary Docker Image
+      uses: docker/[email protected]
+      with:
+        dockerfile: "Dockerfile"
+        always_pull: true
+        tag_with_ref: true
+        repository: expediagroup/apiary-metastore-core
+        username: ${{ secrets.DOCKER_HUB_USERNAME }}
+        password: ${{ secrets.DOCKER_HUB_PASSWORD }}
+        push: ${{ startsWith(github.ref, 'refs/tags/') }}
+
+  apiary-init-docker-image:
+    name: Apiary Init Container Docker Release
+    runs-on: ubuntu-18.04
+    steps:
+    - name: Check out code  
+      uses: actions/checkout@v2
+
+    - name: Release Apiary Init Docker Image
+      uses: docker/[email protected]
+      with:
+        path: "initContainer"
+        dockerfile: "initContainer/Dockerfile"
+        always_pull: true
+        tag_with_ref: true
+        repository: expediagroup/apiary-metastore-init-container
+        username: ${{ secrets.DOCKER_HUB_USERNAME }}
+        password: ${{ secrets.DOCKER_HUB_PASSWORD }}
+        push: ${{ startsWith(github.ref, 'refs/tags/') }}