Release Notes:

- Added links to GitHub pull requests to the git blame tooltips, if they
are available.

Screenshot:

(Yes, the icon will be resized! cc @iamnbutler)

![screenshot-2024-04-19-18 31
13@2x](https://github.com/zed-industries/zed/assets/1185253/774af0b3-f587-4acc-aa1e-1846c2bec127)