Improve `testBadOptions` code coverage

[gmlewis]

For methods that contain a string type for one of their parameters, it is easy to add a testBadOptions call to their test functions in order to improve code coverage. For those that don't, it's not as easy.

Looking at #4016, it dawned on me that if a method has no string args but takes an opts parameter that has URL struct tags where at least one of them is of type string, that it may be possible to still call testBadOptions and change one or more of these strings to newlines (\n) in order to create malformed URL strings.

I'm opening this issue to test out this theory and see if code coverage can be improved across the entire repo based on this realization.

[gmlewis]

This might take a bit of experimentation to see if this is really the case, obviously.
If I'm wrong, then we can simply close this issue.

[gmlewis]

Nope, I was wrong. The URL parameters just get quote-encoded like "issues?filter=%0A".
Closing as not feasible.