fix: update isMobilePhone validation for en-SG (#1573)

Co-authored-by: Li Liwei <liwei.li@hreasily.com>

Author: liliwei25

src/lib/isMobilePhone.js

@@ -46,7 +46,7 @@ const phones = {
   'en-PK': /^((\+92)|(0092))-{0,1}\d{3}-{0,1}\d{7}$|^\d{11}$|^\d{4}-\d{7}$/,
   'en-PH': /^(09|\+639)\d{9}$/,
   'en-RW': /^(\+?250|0)?[7]\d{8}$/,
-  'en-SG': /^(\+65)?[689]\d{7}$/,
+  'en-SG': /^(\+65)?[3689]\d{7}$/,
   'en-SL': /^(?:0|94|\+94)?(7(0|1|2|5|6|7|8)( |-)?\d)\d{6}$/,
   'en-TZ': /^(\+?255|0)?[67]\d{8}$/,
   'en-UG': /^(\+?256|0)?[7]\d{8}$/,

test/validators.js

@@ -6263,13 +6263,15 @@ describe('Validators', () => {
       {
         locale: 'en-SG',
         valid: [
+          '32891278',
           '87654321',
           '98765432',
           '+6587654321',
           '+6598765432',
           '+6565241234',
         ],
         invalid: [
+          '332891231',
           '987654321',
           '876543219',
           '8765432',