[clang] [clang][analyzer] Improve documentation of checker 'cplusplus.Move' (NFC) (PR #96295)

[Donát Nagy via cfe-commits]

https://github.com/NagyDonat approved this pull request.

LGTM, thanks for updating the docs!

I only have one minor inline remark about formatting.

https://github.com/llvm/llvm-project/pull/96295