chore: remove usage of deprecated substr (#2157)

Author: ddelgrosso1

src/acl.ts

@@ -303,7 +303,8 @@ class AclRoleAccessorMethods {
       const isPrefix = entity.charAt(entity.length - 1) === '-';
 
       accessMethods.forEach(accessMethod => {
-        let method = accessMethod + entity[0].toUpperCase() + entity.substr(1);
+        let method =
+          accessMethod + entity[0].toUpperCase() + entity.substring(1);
 
         if (isPrefix) {
           method = method.replace('-', '');

src/file.ts

@@ -1465,8 +1465,8 @@ class File extends ServiceObject<File> {
             .split(',')
             .forEach((hashKeyValPair: string) => {
               const delimiterIndex = hashKeyValPair.indexOf('=');
-              const hashType = hashKeyValPair.substr(0, delimiterIndex);
-              const hashValue = hashKeyValPair.substr(delimiterIndex + 1);
+              const hashType = hashKeyValPair.substring(0, delimiterIndex);
+              const hashValue = hashKeyValPair.substring(delimiterIndex + 1);
               hashes[hashType as 'crc32c' | 'md5'] = hashValue;
             });
         }