Replace islamicc with islamic-umalqura in getCanonicalLocales/main.js (Intl402) (#789)

* Replace islamicc with islamic-umalqura

Per discussion in #743, it's implementation-dependent how ismalicc is
canonicalized. However, 'islamic-umalqura' should be treated the same
way by all implementations.

* Remove ar-ma-u-ca-islamic-umalqura per discussion