Resolve "Git LFS only shows User ID not user name"

What does this MR do and why?

This MR improves the words when attempting to remove an LFS lock:

Before

$ git lfs locks
file_1715144490.txt	root	ID:2

$ git lfs unlock file_1715144490.txt
file_1715144490.txt is locked by GitLab User 1

After

$ git lfs locks
file_1715144490.txt	root	ID:2

$ git lfs unlock file_1715144490.txt
file_1715144490.txt is locked by @root

Related to #424574 (closed)