Merge branch 'js/run-command-close-packs'

The run-command API has been updated so that the callers can easily
ask the file descriptors open for packfiles to be closed immediately
before spawning commands that may trigger auto-gc.

* js/run-command-close-packs:
  Close object store closer to spawning child processes
  run_auto_maintenance(): implicitly close the object store
  run-command: offer to close the object store before running
  run-command: prettify the `RUN_COMMAND_*` flags
  pull: release packs before fetching
  commit-graph: when closing the graph, also release the slab

builtin/receive-pack.c

@@ -2578,10 +2578,9 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 			proc.no_stdin = 1;
 			proc.stdout_to_stderr = 1;
 			proc.err = use_sideband ? -1 : 0;
-			proc.git_cmd = 1;
+			proc.git_cmd = proc.close_object_store = 1;
 			proc.argv = argv_gc_auto;
 
-			close_object_store(the_repository->objects);
 			if (!start_command(&proc)) {
 				if (use_sideband)
 					copy_to_sideband(proc.err, -1, NULL);