Firestore.terminate hangs, and never calls callback

### Description

There are certain scenarios where I'll call Firestore's terminate function, and it will hang, never calling the callback. I haven't been able to create a reproducer, but can consistently get my product's code to get into this state (not shareable for obvious reasons).

This appears to happen when there's an overload of firestore document changes. I am able to see that the `com.google.firebase.firestore` queue's target queue is `com.apple.root.default-qos.overcommit` though not sure what this means. It looks like the queue starts with this value set as the target queue, could be a red herring.

Here's a screenshot of the backtrace of where firestore hangs... It looks like it's unable to close the gRPC watch stream for the RemoteStore, stuck on WaitUntilOffQueue.

I'm basically stuck trying to debug this to see where things go wrong and what I can do to avoid this. I'm very unfamiliar with this codebase, so I don't even know what to look for to find where the code is getting stuck. Any help with pointers on where to look or what to check would be very appreciated.

### Reproducing the issue

Can't share reproduction steps, as I can't share the relevant code.

### Firebase SDK Version

10.22

### Xcode Version

15.3

### Installation Method

CocoaPods

### Firebase Product(s)

Firestore

### Targeted Platforms

iOS

### Relevant Log Output

```shell
There are no relevant logs.
```

### If using Swift Package Manager, the project's Package.resolved

None

### If using CocoaPods, the project's Podfile.lock

Can't share