[FEA] Add premerge checks for checking unshimmed classes for binary differences between shims

[NVnavkumar]

Build issues like #9571 usually arise from compiling and recompiling classes that result in different bytecode versions of classes that are "unshimmed" (that is classes that should be shared between shims without any bytecode differences). This can happen due to creating dependencies on shim classes when they cannot exist and now even differences between Scala compilers, and other build issues with parallel worlds.

We should add a check for these bytecode differences between different shim versions on unshimmed classes that can occur.

See #9571 (comment) for a basic reproduce of the original error and other notes on the build.