Update build.yml: refine push event triggers to only run on the main branch and add workflow_dispatch support

Author: pfhuillet

.github/workflows/build.yml

@@ -2,12 +2,13 @@ name: Build
 
 on:
   push:
-    branches: ['**']           # Only run on branches
-    tags-ignore: ['*']         # Ignore all tags
     paths-ignore: ['**.md', '.vscode/**','docs/**','pictures/**']
+    branches:
+      - main        # Only run on branches
   pull_request:
     types: [opened, synchronize, reopened]
     paths-ignore: ['**.md', '.vscode/**','docs/**','pictures/**']
+  workflow_dispatch:
 
 env:
   TOOL4D_PRODUCT_LINE: '20Rx'