Detect obfuscated map reads

[jzbrooks]

Tracking a list of obfuscated map reads that might be valuable to consider in the map assertion checks:

• map.entries.map { it.key }

Ref #5

[jzbrooks]

I think the question becomes where do we stop with trying to figure out all possible obfuscation cases. People can do silly things to avoid detection, but I lean toward the lint checks assuming competence & good faith consideration of alternatives. Trying to cover strange cases can tend to suggest that the check covers all cases. That's great when possible, but if we can't be sure that we cover all the strange cases, it might be better to cover the normative cases (really cases that are the proper use of a particular API surface) and leave the strange cases for either code review or lint checks purpose built to smoke out odd/bad uses.

[jzbrooks]

This originally came from #5 (review)