Update number-to-string.ts

Author: natrajant

src/value-converters/number-to-string.ts

@@ -1,8 +1,3 @@
-/*
-Copyright 2020, Verizon Media
-Licensed under the terms of the MIT license. See the LICENSE file in the project root for license terms.
-*/
-
 export class NumberToStringValueConverter {
     public toView(value) {
         if (value === null || value === '') return null;