Long extension code in TW breaks roundrip tests

[mniip]

C.f. comment at "with International produces a parseable result (if no ext)" in https://github.com/typeable/libphonenumber/blob/main/test/Spec.hs

[mniip]

Upstream issue https://issuetracker.google.com/issues/395520098

[mniip]

Upstream marked this as WONTFIX.