Upgrade classmate from 1.3.4 to 1.5.1

In https://github.com/wildfly/wildfly/pull/12796 we discussed upgrading classmate but as it affected a lot of subsystems and wasn't really needed for the main purpose of that PR (which was urgent) it got dropped and then we never came back to it. But AFAICT the general consensus in the discussion is it was ok to do.

So let's try again.

https://github.com/FasterXML/java-classmate/compare/classmate-1.3.4..classmate-1.5.1
https://github.com/FasterXML/java-classmate/compare/classmate-1.3.4..classmate-1.5.1#diff-780b48c08acd302f35338634f56df2ae