Remove unused import

Author: npalaska

lib/pbench/server/api/resources/pbench_users.py

@@ -1,6 +1,6 @@
 
 from flask import request, jsonify, make_response
-from flask_restful import Resource, abort
+from flask_restful import Resource
 from pbench.server.api import app, bcrypt, db, blacklist
 from pbench.server.api.resources.db_models import UserModel
 from flask_jwt_extended import jwt_required