[clang-tools-extra] [clang-tidy] Add check 'bugprone-assignment-in-selection-statement' (PR #180219)

[Balázs Kéri via cfe-commits]

balazske wrote:

Something is again wrong with the linter test, where are the failures visible (other than looking at raw output at "View details")? It seems that a "line too long" is found in list.rst where all other lines are in the same long format so I do not like to change a single line and it would be much less readable.

https://github.com/llvm/llvm-project/pull/180219