Add `isOneOf` method to `ChiselEnum` (backport #1966) (#2022)

* Add `isOneOf` method to `ChiselEnum` (#1966)

* Add @ekiwi's code as a starting point

* Add test for ChiselEnum isOneOf method

* Make isOneOfTester naming consistent with other testers

* Add scaladoc comments for isOneOf

* Add isOneOf tests that use the method that takes variable number of args

* Add guide level documentation example for isOneOf

(cherry picked from commit bb520b85

)

* Turn on autoclonetype2 for mdocs

Co-authored-by: Verneri Hirvonen <11316555+chiplet@users.noreply.github.com>
Co-authored-by: Jack Koenig <koenig@sifive.com>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>