Add github workflow for auto release (opensearch-project#712)

Signed-off-by: Ankit Kala <[email protected]>

.github/workflows/auto-release.yml

@@ -0,0 +1,29 @@
+name: Releases
+
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    steps:
+      - name: GitHub App token
+        id: github_app_token
+        uses: tibdex/[email protected]
+        with:
+          app_id: ${{ secrets.APP_ID }}
+          private_key: ${{ secrets.APP_PRIVATE_KEY }}
+          installation_id: 22958780
+      - name: Get tag
+        id: tag
+        uses: dawidd6/action-get-tag@v1
+      - uses: actions/checkout@v2
+      - uses: ncipollo/release-action@v1
+        with:
+          github_token: ${{ steps.github_app_token.outputs.token }}
+          bodyFile: release-notes/opensearch.release-notes-${{steps.tag.outputs.tag}}.md