Filter environments for user with given project id

Previously, calling `Environment.for_user(user, project)` would return
environments a user has access to across all projects. Now, we will only
return the relevant environements. This was the cause of a visual bug
where extra environments were shown in the project list.

atst/domain/environments.py

@@ -44,7 +44,7 @@ class Environments(object):
             .join(EnvironmentRole)
             .join(Project)
             .filter(EnvironmentRole.user_id == user.id)
-            .filter(Project.id == Environment.project_id)
+            .filter(Environment.project_id == project.id)
             .all()
         )