SQOOP-3055 MYSQL tests are failing due to the tests ignoring specified username, password and dbname, trying to connect to specified host using "currentUser"

MYSQL test are using option.setUser(MySQLTestUtils.getcurrentUser()), where MySQLTestUtils.getCurrentUser() return
System.getenv("USER");
or
..
whoamiArgs[0] = "whoami";
..
p = Runtime.getRuntime().exec(whoamiArgs);

Whereas it should use the userName and userPass as specified if called with -D parameters (if they are specified, otherwise should fall back to ).

Currently the tests could only run when using localhost + root.