add workflow to publish docs

.github/workflows/publish_docs.yml

@@ -0,0 +1,29 @@
+name: Publish to GitHub Pages
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  publish:
+    if: github.repository == 'software-mansion/react-native-executorch'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out
+        uses: actions/checkout@v1
+
+      - name: Generate docs
+        run: >-
+          git config --local user.email "[email protected]"
+          && git config --local user.name "GitHub Action"
+          && cd docs
+          && yarn
+          && yarn build
+
+      - name: Publish generated content to GitHub Pages
+        uses: JamesIves/github-pages-deploy-action@releases/v3
+        with:
+          FOLDER: docs/build
+          BRANCH: gh-pages
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}