Re: [PATCH] Optimize the description of the configuration in packfile-uris doc

There is a description problem in the document about packfile-uris. This
patch describes the configuration format of `uploadpack.blobPackfileUri`
more accurately.

Thanks for noticing this. The diff itself is correct, of course.

As for the commit message, limit the title to 50 characters or fewer if
possible. Maybe something like "packfile-uri.txt: fix blobPackfileUri
description" or something like that.

Also in the commit message, maybe mention that the correct format can be
seen in t5702.