[ThreadSafety] Ignore parameter destructors (#170843)
Fixes a false positive in thread safety analysis when function
parameters have lock/unlock annotations in their constructor/destructor.
PR #169320 added destructors to the CFG, which introduced false
positives in thread safety analysis for function parameters. According
to [expr.call#6](https://eel.is/c++draft/expr.call#6), parameter
initialization occurs in the caller's context while destruction occurs
in the callee's context.
```cpp
class A {
public:
A() EXCLUSIVE_LOCK_FUNCTION(mu_) { mu_.Lock(); }
~A() UNLOCK_FUNCTION(mu_) { mu_.Unlock(); }
private:
Mutex mu_;
};
int do_something(A a) { // Previously: false positive warning
return 0;
}
```
Previously, thread safety analysis would see the destructor (unlock) in
`do_something` but not the corresponding constructor (lock) that
happened in the caller's context, causing a false positive.
