[clang-tidy] Check request: redundant nullptr assignment in destructor

[denzor200]

Assume we have a class A with destructor like this:

~A() {
   delete raw;
   raw = nullptr; // INCORRECT
}

The line raw = nullptr; is redundant and should be removed since in valid code we never have any reference to A's object once it's descructor has been called.

[chrchr-github]

This could be extended to any member assignment without side effects in a destructor.