[clang] [Clang][Sema] Properly get captured 'this' pointer in lambdas with an explicit object parameter in constant evaluator (PR #81102)

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https://github.com/cor3ntin commented:

LGTM but I'll let @AaronBallman approve as I'm in a flight with bad internet today.

https://github.com/llvm/llvm-project/pull/81102