Add more options for nightly branch builds

Author: xtremekforever

.github/workflows/build-swift-nightly.yml

@@ -10,7 +10,9 @@ on:
         default: 'development'
         type: choice
         options:
+          - swift-6.0-branch
           - swift-6.1-branch
+          - swift-6.2-branch
           - development
       distribution:
         description: 'Distribution'