404 when trying to use "Raw file content" API with branch containing dots in name

Summary

If a branch name contains dots (e.g., 0.1.0), the "raw file content" API returns a 404, even if the file exists.

Steps to reproduce

1. Create a branch 0.1.0 in a repository containing a file (e.g., README.md)
2. Use the Raw file content API endpoint to try and fetch the file

• E.g., `GET https://gitlab.com/api/v3/projects/janslow%2ftest/repository/blobs/0.1.0?filepath=README.md

curl -X GET -H "PRIVATE-TOKEN: ****" -H "Cache-Control: no-cache" "https://gitlab.com/api/v3/projects/janslow%2ftest/repository/blobs/0.1.0?filepath=README.md"

Expected behavior

It should return the contents of the file/blob

Actual behavior

Returns a HTTP 404 status

{
  "error": "404 Not Found"
}

Output of checks

This bug happens on GitLab.com