Revert "[cloud] Fix invitation bugs"
Created by: bobheadxi
Reverts sourcegraph/sourcegraph#31727
I'm seeing this failure in my branches: https://buildkite.com/sourcegraph/sourcegraph/builds/134505#cd00284a-9139-4378-9e03-b879d81f6a32/109-2397
FAIL | Migrations/frontend/idempotent_down (0.50s)
Test plan: https://buildkite.com/sourcegraph/sourcegraph/builds/134525 should pass