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

test/intl402/Intl/getCanonicalLocales/main.js

@@ -29,6 +29,4 @@ assertArray(gCL({'a': 0}), []);
 
 assertArray(gCL({}), []);
 
-assertArray(gCL(['ar-ma-u-ca-islamicc']), ['ar-MA-u-ca-islamicc']);
-
 assertArray(gCL(['th-th-u-nu-thai']), ['th-TH-u-nu-thai']);