Fix the syntax differences between HSQL and Postgres

webgoat-lessons/sql-injection/src/main/resources/db/migration/V2019_09_26_7__employees.sql

@@ -14,7 +14,7 @@ INSERT INTO employees VALUES ('34477','Abraham ', 'Holman',  'Development', 5000
 INSERT INTO employees VALUES ('37648','John',     'Smith',   'Marketing',   64350, '3SL99A');
 
 CREATE TABLE access_log (
-  id int not null primary key identity,
+  id int not null primary key,
   time varchar(50),
   action varchar(200)
 );