Removes instanceof ObjectType checks from method signatures in System.qll to support
nullable reference types (object?). This fixes false positives when Equals(object?)
is used instead of Equals(object), as they are the same underlying type with different
nullability annotations.
Fixes:
- SystemIComparableInterface.getCompareToMethod()
- SystemObjectClass.getEqualsMethod()
- SystemObjectClass.getStaticEqualsMethod()
- SystemObjectClass.getReferenceEqualsMethod()
Co-authored-by: hvitved <3667920+hvitved@users.noreply.github.com>