This PR continues the work in #17125 by progressively ensuring that git
commands run within the request context.
This now means that the if there is a git repo already open in the context it will be used instead of reopening it.
Signed-off-by: Andrew Thornton <art27@cantab.net>
In investigating #7947 it has become clear that the storage component of go-git repositories needs closing.
This PR adds this Close function and adds the Close functions as necessary.
In TransferOwnership the ctx.Repo.GitRepo is closed if it is open to help prevent the risk of multiple open files.
Fixes#7947
