test-lfs: dial up the debugging on commands that interact with the server This will be useful to let the client print out the HTTP headers and JSON in a future patch, so we can compare native LFS serving against test-lfs-server behavior. There tends to be a lot of debug stuff that we don't care about here in a push, so I was tempted to print this output with a [devel] config. But this will be useful for field debugging too, so just put up with the extra output here. It would have been nice to be able to set ui.debug once, but issue5815 prevents that.