Fix #14990: FP memleak with function call through function pointer

[aadanen]

Modify checkleakautovar to consider calls to lambdas and function pointers as function calls that can allow resources to escape the current scope.

[aadanen]

I am suprised to see all these segmentation faults. In my testing everything seemed to work nicely but I guess it was just crashing silently and working properly. I will need to modify functionCall() more heavily to not send nullptr to the library functions. This kinda undermines my idea of reusing functionCall for anonymous functions but I still think it is better than duplicating the function.

[aadanen]

I switched from the makefile to cmake and ran the CI workflows locally so I think next time they run, they should pass. Sorry about that. Also I noticed that git was using my work account, so I sorted that out too.

[danmar]

I am not sure why but there was significant slowdown in CI (selfchecking) after this?

[aadanen]

Thanks for the review! I will look into it more on monday.

[aadanen]

I found the issue with the selfcheck slowdown. isAnonymousFunctionCall would sometimes link() backwards causing the checker to loop forever.

void f(char ch16) {
    ch = static_cast<unsigned char>(((ch16 >= 0x80) ? 0xff : ch16));
}

[aadanen]

the sanitizers/build check failed because of some network thing:
Connecting to apt.llvm.org (apt.llvm.org)|2a04:4e42:8a::561|:443... failed: Network is unreachable.
I think it probably just needs to be re-run.

Thanks!