Merge branch 'jt/fetch-remove-lazy-fetch-plugging'

"git fetch" codepath had a big "do not lazily fetch missing objects when I ask if something exists" switch. This has been corrected by marking the "does this thing exist?" calls with "if not please do not lazily fetch it" flag. * jt/fetch-remove-lazy-fetch-plugging: promisor-remote: remove fetch_if_missing=0 clone: remove fetch_if_missing=0 fetch: remove fetch_if_missing=0