Provide exclusions for default metrics collected

[LukasDeco]

Hello!

I am trying to utilize prom-client in a bun application and unfortunately bun does not yet support the eventLoopLag metric. I just want to be able to exclude this but there doesn't seem to be a way, can I just add some kind of parameter for excluding metrics?

[LukasDeco]

I actually also need to exclude heap space.