feat: (isMobilePhone): add Cameroon fr-CM locale (#1772)

* Add Cameroon validation regex

I have added a regex for validating Cameroonian mobile numbers which should work. I'm not super comfortable with regular expressions, so if I have screwed something up, please let me know. I have done some basic testing and it has functioned fine thus far.

* Update README to include fr-CM in isMobilePhone

* Add (very) basic testing for Cameroonian mobile number

* Fix missing brace (whoops!)

* Fix commas (I hope)

* Fix sloppy tests

Fix my sloppy tests. I'm really tired and probably should not be working on this, but I accidentally added an extra digit while typing.

* Update regex for correctness

Add mobile prefix (6) to regex, remove space allowance, and optimize regex

* Update tests for correctness

* Remove invalid space

Sorry!

* Rerun failed tests (internal server error)

src/lib/isMobilePhone.js

@@ -77,6 +77,7 @@ const phones = {
   'fi-FI': /^(\+?358|0)\s?(4(0|1|2|4|5|6)?|50)\s?(\d\s?){4,8}\d$/,
   'fj-FJ': /^(\+?679)?\s?\d{3}\s?\d{4}$/,
   'fo-FO': /^(\+?298)?\s?\d{2}\s?\d{2}\s?\d{2}$/,
+  'fr-CM': /^(\+?237)6[0-9]{8}$/,
   'fr-FR': /^(\+?33|0)[67]\d{8}$/,
   'fr-GF': /^(\+?594|0|00594)[67]\d{8}$/,
   'fr-GP': /^(\+?590|0|00590)[67]\d{8}$/,

test/validators.js

@@ -7592,6 +7592,21 @@ describe('Validators', () => {
           '088-320000',
         ],
       },
+      {
+        locale: 'fr-CM',
+        valid: [
+          '+237677936141',
+          '237623456789',
+          '+237698124842',
+          '237693029202',
+        ],
+        invalid: [
+          'NotANumber',
+          '+(703)-572-2920',
+          '+237 623 45 67 890',
+          '+2379981247429',
+        ],
+      },
       {
         locale: 'ko-KR',
         valid: [