[clang-tools-extra] [NFC] Complete proper copying and resource cleanup in classes. (PR #118655)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman commented:

I don't think any of these changes are strictly necessary (they're not fixing any bugs), but I do think they may be somewhat reasonable as an NFC cleanup if we're explicitly marking functions as deleted because we don't intend for the type to be used as a value type. WDYT @HerrCai0907 ?

https://github.com/llvm/llvm-project/pull/118655