Add release workflow

Author: psrpinto

.github/workflows/.gitignore

@@ -0,0 +1 @@
+.secrets

.github/workflows/release.yml

@@ -0,0 +1,55 @@
+# Create a draft release when a tag is pushed
+name: Create a release
+
+on:
+  # Allow manual trigger from the Actions tab:
+  # https://github.com/Automattic/wp-openid-connect-server/actions/workflows/release.yml
+  workflow_dispatch:
+
+  push:
+    tags: ['v*']
+
+jobs:
+  create-release:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Install composer dependencies
+        run: composer install --no-ansi --no-dev --no-interaction --no-plugins --no-scripts --optimize-autoloader
+
+      - name: Generate readme.txt
+        run: php bin/transform-readme.php
+
+      - name: Create directory for release
+        run: mkdir /tmp/release
+
+      - name: Copy all files to release directory
+        run: cp -r ./* /tmp/release/
+
+      - name: Remove unnecessary files and directories
+        run: |
+          rm -rf /tmp/release/.github
+          rm -rf /tmp/release/.git
+          rm -rf /tmp/release/bin
+          rm -rf /tmp/release/README.md
+          rm -rf /tmp/release/.wp-env.json
+          rm -rf /tmp/release/phpcs.xml
+
+      - name: Move and rename release directory
+        run: mv /tmp/release wp-openid-connect-server
+
+      - name: Create archive for release
+        run: tar -cvzf wp-openid-connect-server-${{ github.ref_name }}.tar.gz wp-openid-connect-server
+
+      - name: Create release
+        uses: ncipollo/release-action@v1
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          tag: ${{ github.ref_name }}
+          artifacts: "wp-openid-connect-server-${{ github.ref_name }}.tar.gz"
+          artifactErrorsFailBuild: true
+          draft: true