Update R-package-ubuntu.yml

Author: sorenwacker

.github/workflows/R-package-ubuntu.yml

@@ -2,9 +2,9 @@ name: Install on Ubuntu 24.04
 
 on:
   push:
-    branches: [ "main" ]
+    branches: [ "" ]
   pull_request:
-    branches: [ "main" ]
+    branches: [ "" ]
 
 permissions:
   contents: read