Update DG Toolkit to JDK 17 LTS

[nmandrescu]

It is planned for September 2021.

[developster]

Removed cglib from classpath.

There was an error in revisions panel because AbstractPropertyModel was trying to make Enum.name writable. Replaced with a read only LambdaModel.

Could not test jersey since we are not using it in the toolkit directly.

Tested dummy endpoint and it works as expected, Jackson didn't crash the app.

[nmandrescu]

1. The main change is Wicket upgrade from 9.3 to the latest: since 9.5 release (Sept 12th 2021) cglib dependency was removed for JDK17 compatibility WICKET-6913.

2. For reference, this was previously reported by Jackson at startup. Retested using Cashew-IN with latest libs and JDK17 and it is no longer reported:

WARNING: Illegal reflective access by com.fasterxml.jackson.databind.util.ClassUtil (file:~/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.12.3/jackson-databind-2.12.3.jar) to field java.lang.reflect.Proxy.h
WARNING: Illegal reflective access by com.fasterxml.jackson.databind.util.ClassUtil (file:~/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.12.3/jackson-databind-2.12.3.jar) to field java.lang.ref.Reference.referent
WARNING: Illegal reflective access by com.fasterxml.jackson.databind.util.ClassUtil (file:~/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.12.3/jackson-databind-2.12.3.jar) to field java.lang.ref.Reference.queue
WARNING: Illegal reflective access by com.fasterxml.jackson.databind.util.ClassUtil (file:~/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.12.3/jackson-databind-2.12.3.jar) to field java.lang.ref.Reference.next
WARNING: Illegal reflective access by com.fasterxml.jackson.databind.util.ClassUtil (file:~/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.12.3/jackson-databind-2.12.3.jar) to field javax.naming.InitialContext.myProps
WARNING: Illegal reflective access by com.fasterxml.jackson.databind.util.ClassUtil (file:~/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.12.3/jackson-databind-2.12.3.jar) to field javax.naming.InitialContext.defaultInitCtx
WARNING: Illegal reflective access by com.fasterxml.jackson.databind.util.ClassUtil (file:~/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.12.3/jackson-databind-2.12.3.jar) to field javax.naming.InitialContext.gotDefault

Heads up: upgrading a DG Toolkit based app from JDK8/11 also requires other migration (many done preliminary with JDK16 in #365 when JDK17 wasn't yet released).

[developster]

Tested dg-toolkit for warnings from Jackson and logs are clean.