Add new GraphQL types for budget investments

- added 2 new types
- modified the models to get data through graphQL
- modified the corresponding spec
- also testing that hidden comments do not show up
- modified comments specs bc now it returns comments on budget
  investments

docs/en/features/graphql.md

@@ -130,6 +130,8 @@ The models are the following:
 | `User`                  | Users                         |
 | `Debate`                | Debates                       |
 | `Proposal`              | Proposals                     |
+| `Budget`                | Participatory budgets         |
+| `Budget::Investment`    | Budget investments            |
 | `Comment`               | Comments on debates, proposals and other comments |
 | `Geozone`               | Geozones (districts)          |
 | `ProposalNotification`  | Notifications related to proposals |

docs/es/features/graphql.md

@@ -130,6 +130,8 @@ La lista de modelos es la siguiente:
 | `User`                  | Usuarios                     |
 | `Debate`                | Debates                      |
 | `Proposal`              | Propuestas                   |
+| `Budget`                | Presupuestos participativos  |
+| `Budget::Investment`    | Proyectos de gasto           |
 | `Comment`               | Comentarios en debates, propuestas y otros comentarios |
 | `Geozone`               | Geozonas (distritos)         |
 | `ProposalNotification`  | Notificaciones asociadas a propuestas |