fixes#11950https://github.com/coder/coder/issues/11950#issuecomment-1987756088 explains the bug
We were also calling into `Unlisten()` and `Close()` while holding the mutex. I don't believe that `Close()` depends on the notification loop being unblocked, but it's hard to be sure, and the safest thing to do is assume it could block.
So, I added a unit test that fakes out `pq.Listener` and sends a bunch of notifies every time we call into it to hopefully prevent regression where we hold the mutex while calling into these functions.
It also removes the use of a `context.Context` to stop the PubSub -- it must be explicitly `Closed()`. This simplifies a bunch of the logic, and is how we use the pubsub anyway.
* chore: add /v2 to import module path
go mod requires semantic versioning with versions greater than 1.x
This was a mechanical update by running:
```
go install github.com/marwan-at-work/mod/cmd/mod@latest
mod upgrade
```
Migrate generated files to import /v2
* Fix gen
* chore: rename store to dbmock for consistency
* chore: remove redundant dbtype package
This wasn't necessary and forked how we do DB types.
* chore: separate pubsub into a new package
This didn't need to be in database and was bloating it.
