Block coin miners by default with Brave shields up

[bbondy]

This is done once this is merged: brave-experiments/ad-block#74

Testing notes:

1. Close Brave
2. Use new test data file uploaded to the PR.
3. Open Brave
4. Visit https://cnhv.co/6or
5. Turn off shieods

Step 4 should not load the page, but if you turn shields down it will.

[bbondy]

This is live now, you can see it even with the currently released build since it is from an adblock definition update.

[srirambv]

Any specific QA test required?

[bbondy]

@srirambv yep I had it in the commit but I just updated it in comment 0. Thanks for the ping.