Add create/deploy release Github workflow (#305)

* add github workflows to create and deploy new releases

* update workflow: switch to main branch

.github/workflows/create-deploy-release.yml

@@ -0,0 +1,26 @@
+name: Create and deploy a new release
+run-name: create and deploy ${{ github.sha }}
+on:
+  push:
+    branches:
+      - main
+jobs:
+  trigger-gitlab-pipeline:
+    runs-on: ubuntu-latest
+    env:
+      GITLAB_API_TOKEN: ${{ secrets.GITLAB_API_TOKEN }}
+    steps:
+      - name: configure environment
+        shell: bash
+        run: |
+          echo "REPO_PUBLIC_URL=${{ github.server_url }}/${{ github.repository }}.git" >> $GITHUB_ENV
+          echo "SCAFFOLD_DIR=scaffold" >> $GITHUB_ENV
+      - name: clone scaffold repository
+        shell: bash
+        run: git clone --depth 1 https://oauth2:$GITLAB_API_TOKEN@${{ vars.SCAFFOLD_REPO_PUBLIC_URL }} ${{ env.SCAFFOLD_DIR }}
+      - name: trigger Gitlab CI/CD pipeline
+        shell: bash
+        run: |
+          RELEASE_VERSION="${GITHUB_SHA:0:8}"
+          ./scripts/gitlab-ci-pipeline.sh ${{ env.REPO_PUBLIC_URL }} ${{ vars.APP_NAME }} $RELEASE_VERSION
+        working-directory: ${{ env.SCAFFOLD_DIR }}