
The go-git module (and helper modules) recently moved from `gopkg.in/src-d/go-git` to `github.com/go-git/go-git` [0]. This commit switches to the new module, as well as uplifts from v4 to v5. [0] https://github.com/src-d/go-git/issues/1295#issuecomment-592965250 Change-Id: I2e73ba7bb1220a3c75c0d81aa5ab0f1f13479161