Merge branch 'ew/gc-auto-pack-limit-fix' into maint

"gc.autoPackLimit" when set to 1 should not trigger a repacking
when there is only one pack, but the code counted poorly and did
so.

* ew/gc-auto-pack-limit-fix:
  gc: fix off-by-one error with gc.autoPackLimit

builtin/gc.c

@@ -177,7 +177,7 @@ static int too_many_packs(void)
 		 */
 		cnt++;
 	}
-	return gc_auto_pack_limit <= cnt;
+	return gc_auto_pack_limit < cnt;
 }
 
 static void add_repack_all_option(void)