Bugprone Tick time monitoring

[Petzep]

Describe the bug
The time measurement of a tick is bug-prone.

BehaviorTree.CPP/src/tree_node.cpp

Lines 109 to 111 in 2a8a226

	auto t1 = steady_clock::now();
	new_status = tick();
	auto t2 = steady_clock::now();

This way of measuring time can be reordered by the compiler and will result in a time difference of 0.
A good explanation of this issue can be found here:
Enforcing statement order in C++

The article also discusses a fix.

And I've also seen examples where they fix it with an atomic fence (which cost's no extra cylces)
https://stackoverflow.com/questions/22278963/how-to-prevent-timestamp-from-being-reorder-out

[facontidavide]

you are welcome to submit a PR to address this.

[Aglargil]

#863
This might help?