I have recently seen a few customers interested in using Gitea with Looker. It is not one of the officially supported version control services, but I have gotten it to work with their test server. The general process is nearly identical to the GitHub setup with SSH. The only key difference is that in the Git Connection setting, we want to select Custom Git Configuration.
In essence, we want to launch Gitea.
Create a repository.
Name the repo, set the privacy level, and select the desired license.
Click SSH and grab the link:
Add that to your Looker project, click continue and select Custom Git Configuration.
Grab the Deploy Key from Gitea by going to settings, and deploy keys. Click Add Deploy Key and paste the key provided by Looker into the text box.
Go back to Looker to finalize the setup and test the Git connection!
You should be all set.