Include graphics objects with hidden handles in axes limit calculation (bug #63095). * libinterp/corefcn/graphics.cc (get_children_limits): Get handles to all axes children including those with hidden handle visibility. Add BIST. * libinterp/corefcn/graphics.in.h (text::update_position): Do not automatically change "zliminclude" property. Axes labels are implemented as text objects, and we don't want their extent to be included in the axis limit calculation.

%!test <*59704>
%! o = bug59704_1 ();
%! o.test ();
%! assert (o.p, [])

%!test <*59704>
%! o = bug59704_2 ();
%! [~, o(1)] = size (rand (2, 5));
%! assert (o(1), 5)