Fix random concurrency issue

[mcred]

Occasionally when re-running the git extension with an already existing repo, this error could occur:

Task java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask@5f2c773b[Not completed, task = java.util.concurrent.Executors$RunnableAdapter@5e5be0aa[Wrapped task = org.eclipse.jgit.lib.RepositoryCache$$Lambda$933/0x00007fd8e7618430@3e55a0a6]] rejected from java.util.concurrent.ScheduledThreadPoolExecutor@1e97af5a[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 1]

Re-ordering and putting repository.close() in the finally clause fixes it.