DefaultRecordMapper should check whether user is attempting to map into an inner class

[lukaseder]

The DefaultRecordMapper cannot instantiate inner classes via reflection, as it doesn't know anything about an enclosing instance. E.g. this isn't possible:

class Outer {
    class Inner {}
}

And then

ctx.resultQuery("...").fetchInto(Outer.Inner.class);

Users will have to make their nested classes static, e.g.

class Outer {
    static class Inner {}
}

This can easily be forgotten, because of Java's ill chosen default of making nested classes inner classes. It would be nice if the DefaultRecordMapper could check this:

clazz.isMemberClass() && !Modifier.isStatic(clazz.getModifiers());

And add a debug message to the list of messages from #11794

[lukaseder]

Fixed in jOOQ 3.17.0, 3.16.7 (#13583), and 3.15.11 (#13584)