investigate issue with deserializing Maps with Scala 2 Enums as keys (when using Scala 3)

[pjfanning]

This test passes with Scala 2 but fails with Scala 3.

• https://github.com/FasterXML/jackson-module-scala/blob/master/src/test/scala-2.%2B/com/fasterxml/jackson/module/scala/deser/EnumerationScala2DeserializerTest.scala