Something invalidating `Enzyme.__init__` causes a heavy package load time penalty

When loading OmniPackage.jl(https://github.com/JuliaComputing/OmniPackage.jl/) a big part of its load time (around 10s) is spent compiling and running the `__init__` method in Enzyme, profile available at https://kristofferc.github.io/tracy-traces/omnipackage/.

Ideally, Enzyme would somehow protect itself against this, by either making the code in `__init__` less vulnerable to invalidations or some other way (maybe using a frozen world age).

cc @vchuravy