Git worktree support - updated JGit

[Axinet]

Hello @rudikershaw ,

It seems like JGit finally added partial support for worktrees: https://projects.eclipse.org/projects/technology.jgit/releases/7.0.0
"Add worktrees read support". I am not sure whether is it enough for hooks installation or not (I don't know whether obtaining location from the API would be enough to install hooks).
Current support by just ignoring such configuration took me quite a time to find out why hooks are not present despite configuraing the plugin ;) (#44).
It would be nice if you could verify whether it makes possibility to support worktree more feasible.