`unicorn/no-unnecessary-polyfills` is slow

The rule itself is working fine as is as far as I can tell, it is just one of the slowest rules for our codebase while we have many eslint rules enabled of different plugins.

It takes more than one second just for that single rule to run on https://github.com/DataDog/dd-trace-js.

I did not verify the reason, I just guessed it is likely possible to improve the performance.