Add flag to filter out URLs you don't want to be tested

[JohnEidum]

This PR allows you to filter out certain URLs that you would like to be skipped over during testing. This is used alongside staticDistDir and is not functional with url (Not sure how exactly that would end up working).

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[JohnEidum]

@googlebot I signed it!

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[JohnEidum]

@googlebot I fixed it.

[patrickhulce]

thanks very much @JohnEidum! this functionality sounds good, just some naming and code clarity points :)

[JohnEidum]

Thank you! I have made the necessary changes. I chose to go with autodiscoverUrlBlocklist.

[patrickhulce]

thanks @JohnEidum 🎉

[patrickhulce]

sorry @JohnEidum you have one more annoying snapshot to update with help text whitespace padding