Mapeamento objeto relacional + seed banco

Fazer o mapeamento padrão ManyToMany com a tabela de associação e fazer o seed do banco:

INSERT INTO tb_user (first_name, last_name, email, password) VALUES ('Alex', 'Brown', '[e-mail]', '$2a$10$eACCYoNOHEqXve8aIWT8Nu3PkMXWBaOxJ9aORUYzfMQCbVBIhZ8tG');
INSERT INTO tb_user (first_name, last_name, email, password) VALUES ('Maria', 'Green', '[e-mail]', '$2a$10$eACCYoNOHEqXve8aIWT8Nu3PkMXWBaOxJ9aORUYzfMQCbVBIhZ8tG');

INSERT INTO tb_role (authority) VALUES ('ROLE_OPERATOR');
INSERT INTO tb_role (authority) VALUES ('ROLE_ADMIN');

INSERT INTO tb_user_role (user_id, role_id) VALUES (1, 1);
INSERT INTO tb_user_role (user_id, role_id) VALUES (2, 1);
INSERT INTO tb_user_role (user_id, role_id) VALUES (2, 2);