Fetch on Bare are Not Only Changes

Recently, I discovered that when I fetch a bare local repo, I often fetch a large number of git objects from remote to local (if there has some changed). However, most of the fetched objects already exist on the local side (not only changes).

This will cause my bare repo size to increase The bigger it is, the more time will be wasted waiting for network transmission

Expected behavior

Fetch only changes objects.

Actual behavior

Fetch a lot of object even it's already exists on the local repo.

0.26.2
Operating system(s) tested;

Windows11, NetFrameWork 4.7.2

该 issue 没有指定源文件、测试或入口点。在 Windows 11 上使用 .NET Framework 4.7.2 和版本 0.26.2，复现一次从本地 bare 仓库进行的 fetch，并将传输的对象与已经存在的对象进行比较；仅获取缺失的对象时即完成。