Update publish-luarocks.yaml workflow

Author: bytexenon

Diff for: .github/workflows/publish-luarocks.yaml

@@ -1,26 +1,35 @@
 name: LuaRocks Release
+
 on:
-  release:
-    types: [created, published, edited]
+  push:
+    branches:
+      - main
+
 jobs:
   release:
     runs-on: ubuntu-latest
+
     steps:
     - name: Checkout code
       uses: actions/checkout@v2
+
     - name: Set up Lua
       uses: leafo/gh-actions-lua@v8
       with:
         luaVersion: "5.4.0"
+
     - name: Delete old rockspec files
       run: |
         git rm MathParser-*.rockspec || true
+
     - name: Generate rockspec
       run: |
         lua build/generate_rockspec.lua ${GITHUB_REF#refs/tags/}
+
     - name: Upload to LuaRocks
       run: |
         luarocks upload --api-key ${{ secrets.LUAROCKS_API_KEY }} MathParser-${GITHUB_REF#refs/tags/}.rockspec
+
     - name: Add rockspec to repository
       run: |
         git config --local user.email "[email protected]"