New API endpoint `import/gitea`
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Numerous Gitea repositories imports are hardly doable through the web interface, and an api endpoint would be a great improvment.
In the process of migrating around 1500 repositories from gitea to gitlab, I patched my own gitlab to make this endpoint work and thus proposing this improvement in !145234 This MR needs specs added to be complete.
I open the issue here to smooth the process of reviewing the PR by the team
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