ci(docs): only publish site on release (#2322)

.github/workflows/deploy.yml

@@ -33,6 +33,20 @@ jobs:
         env:
           COMMITTER_TOKEN: ${{ secrets.HOMEBREW_GITHUB_API_TOKEN }}
 
+  publish_docs:
+    name: Publish docs to Netlify
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Setup | Checkout
+      uses: actions/checkout@master
+
+    - name: Publish
+      uses: netlify/actions/build@master
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        NETLIFY_SITE_ID: ${{ secrets.NETLIFY_SITE_ID }}
+
   # Build sources for every OS
   github_build:
     name: Build release binaries