I update my addons with git. Here i have multiple localization errors. Here no localizations available?

Using the repository directly will not work, the localisation is done via curseforge and is only inserted when releases are made. If you use a release from GitHub, it should work fine.

If you do want a clone to do changes yourself (PRs welcome!), I suggest downloading a release and pasting Localization/* from the release into the repo (and ignoring the local changes). That's what I do.