[clang] [clang] Make source locations space usage diagnostics numbers easier to read (PR #114999)

[Boaz Brickner via cfe-commits]

bricknerb wrote:

> Do we really care about the exact byte numbers? Maybe we should only show the human-friendly version? It's appealing to have less noise if we can.

Yes, I was considering both options.
It might be useful to see the full number in case you want to diff between logs, and the diff would be relatively small (people might care about zero diff vs. tiny diff), so I decided to make this change not lose any information.

https://github.com/llvm/llvm-project/pull/114999