Repository's initial commit doesn't update repo 'Main branch' which causes the 'Commit', 'Branch' and 'Pull Requests' pages redirect back to Source page

Issue Summary

Repository's initial commit doesn't update repo the 'Main branch' which causes the 'Commit', the 'Branch' and the 'Pull Requests' pages redirect you back to the Source page

Steps to Reproduce

1. Create a repository with API or create a repo through UI(exclude README and .gitignore)
2. From the new repo's Source page, click `Create a README` or `Create a .gitignore` button to create a default initial commit
3. Click 'Commit', 'Branch' or 'Pull Requests' from the left navigation bar

Expected Results

You are redirected to 'Commit', 'Branch' or 'Pull Requests' pages.

Actual Results

You will be redirected to the Source page. 

Workaround

1. Navigate to Repository Settings > Advanced section
2. Update the Main branch field
3. Refresh the repo page