Migrate Jackson 2 to Jackson 3

Let's use this issue to track eventually migrating from Jackson 2 (`com.fasterxml.jackson`) to Jackson 3 (`tools.jackson`).

For background, see https://github.com/FasterXML/jackson/wiki/Jackson-Release-3.0 and https://github.com/FasterXML/jackson/wiki/Jackson-Releases.

As more and more other libraries migrate, it would be good for this one as well to move on (eventually).

This will require adjustments in `import` statements and the `dependency`. Perhaps https://docs.openrewrite.org/recipes/java/jackson/upgradejackson_2_3 is useful (but it may be simple enough to just be done manually).

It should be backwards compatible for users.