progress: stop using the_repository

Stop using `the_repository` in the "progress" subsystem by passing in a
repository when initializing `struct progress`. Furthermore, store a
pointer to the repository in that struct so that we can pass it to the
trace2 API when logging information.

Adjust callers accordingly by using `the_repository`. While there may be
some callers that have a repository available in their context, this
trivial conversion allows for easier verification and bubbles up the use
of `the_repository` by one level.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/remote.c

@@ -820,7 +820,8 @@ static int mv(int argc, const char **argv, const char *prefix,
 		 * Count symrefs twice, since "renaming" them is done by
 		 * deleting and recreating them in two separate passes.
 		 */
-		progress = start_progress(_("Renaming remote references"),
+		progress = start_progress(the_repository,
+					  _("Renaming remote references"),
 					  rename.remote_branches->nr + rename.symrefs_nr);
 	}
 	for (i = 0; i < remote_branches.nr; i++) {