Fix multi-namespace class inheritance transpile bug

[luis-soares-sky]

Fixes a bug with class inheritance where an ancestor 2+ levels higher would get the wrong super index, but only when that ancestor was a namespace-relative reference from a different namespace than the originating class.

Consider this code example

namespace alpha
    class One
    end class
end namespace

namespace beta
    class Two extends alpha.One
    end class

    class Three extends Two
    end class
end namespace

namespace charlie
    class Four extends beta.Three
    end class
end namespace

The inheritance chain for Four is: Four -> beta.Three -> Two -> alpha.One.
The bug occurs when trying to find Two because it's a namespace-relative lookup. BrighterScript was trying to find charlie.Two instead of beta.Two.

This resulted in the wrong super index, causing a stackoverflow at runtime.