fix: one more instance of jet decoding

Author: Vikas Agarwal

src/util/tc.js

@@ -3,7 +3,7 @@
  */
 import { MARATHON_MATCH_SUBTRACKS, CHALLENGE_TRACKS, ALLOWED_USER_ROLES, ADMIN_ROLES } from '../config/constants'
 import _ from 'lodash'
-import jwtDecode from 'jwt-decode'
+import { decodeToken } from 'tc-auth-lib'
 
 export const RATING_COLORS = [{
   color: '#9D9FA0' /* Grey */,
@@ -56,6 +56,6 @@ export const checkAllowedRoles = (roles) => roles.some(val => ALLOWED_USER_ROLES
  * @param  token
  */
 export const checkAdmin = (token) => {
-  const roles = _.get(jwtDecode(token), 'roles')
+  const roles = _.get(decodeToken(token), 'roles')
   return roles.some(val => ADMIN_ROLES.indexOf(val.toLowerCase()) > -1)
 }