Unpin logback version

[febbraiod]

We are doing this now to deal with Grails no longer supporting logback.groovy (which we use in all apps).

Pinning the logback version is the grails' team suggested workaround but the updated gradle grails plugin will throw if it finds the logback.groovy file. Preferably that plugin would match the version of grails we are using (5.2.1 as of this writing).

At some point we'll want to remove both these workarounds somehow.

[lbwexler]

We should be able to remove this workaround now -- virtualdogbert is now providing a solution here to the grails community