Cannot detect memory leaks with new garbage collector

[jtenner]

@willemneal looking at this RTrace output, I can very clearly see that the references sometimes don't properly get collected.

[Success]: ✔ float to int maps
 [Success]: ✔ different sized float to float maps
 [Success]: ✔ object to int maps RTrace: +32
 [Success]: ✔ float to string maps, with emoji RTrace: -25
 [Success]: ✔ negative float to string maps
 [Success]: ✔ int to empty string maps RTrace: -4
 [Success]: ✔ int to complex object maps RTrace: +36
 [Success]: ✔ int to complex object maps, with multiple and circular references RTrace: +2
 [Success]: ✔ int to nullable object maps RTrace: -21
 [Success]: ✔ infinite floats to float maps RTrace: -24

Calling the garbage collector after every test might be worth while.

Thoughts?