[link_course] Arrumados testes do rspec

Signed off by: Lucas Takeshi <lucastakeshipalma@gmail.com>
[link_course] Colocando em ptBR as mensagens de erro nos pedidos de monitoria

Signed off by: Lucas Takeshi <lucastakeshipalma@gmail.com>
[link_course] Testando mensagens de erro do pedido de monitoria

Signed off by: Lucas Takeshi <lucastakeshipalma@gmail.com>
[link_course] Trocando true/false para sim/não

Signed off by: Lucas Takeshi <lucastakeshipalma@gmail.com>
[link_course] Testando a tabela de pedidos de monitoria

Signed off by: Lucas Takeshi <lucastakeshipalma@gmail.com>