Simplify github workflow

Author: dankraw

.github/workflows/ci.yml

@@ -2,9 +2,9 @@ name: CI
 
 on:
   push:
-    branches: [ master, main ]
+    branches: [ master ]
   pull_request:
-    branches: [ master, main ]
+    branches: [ master ]
 
 jobs:
   lint:
@@ -46,7 +46,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go-version: [ '1.20', '1.21', '1.22', '1.25' ]
+        go-version: [ '1.25' ]
         os: [ ubuntu-latest, macos-latest ]
     steps:
       - name: Checkout code