patch 9.1.0673: Vim9: too recursive func calls when calling super-class method

patch 9.1.0673: Vim9: too recursive func calls when calling super-class method

Problem:  Vim9: too recursive func calls when calling super-class method
          with non-overriden super-call methods. (Aliaksei Budavei)
Solution: use interface method, when super is to be used (Ernie Rael)

When compiling "super.Func()" force class context to class that defines
function that is doing "super.Func()".
ISN_METHODCALL arg "cmf_is_super" for specific ufunc.

fixes: #15448
fixes: #15463 (2) super.method may not execute in context of defining
                  class
closes: #15477

Signed-off-by: Ernie Rael <errael@raelity.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>