[Approval] Discussions list does not show first reply on discussion held for approval

## Bug Report

**Current Behavior**
When a first reply is added to a discussion held for approval (posted by a user who does not have Start Discussions without Approval permission), the discussion list retains the "User started X time ago" label instead of updating to display the reply with "User replied x time ago."

Replies by same user or different users appear to demonstrate the same issue. The second reply appears to reset Flarum to its normal behavior, it will then display replies on the discussion list.

**Steps to Reproduce**
1. Create tag with Start Discussion without Approval permission withheld from a group
2. Create a user within said group
3. Post a new discussion in said tag
4. Reply to discussion with any user
5. Check the discussion list, it will not show the first reply

**Expected Behavior**
A clear and concise description of what you expected to happen.

**Screenshots**
[Unapproved Test discussion with 1 reply.](https://i.imgur.com/qWb2eF6.png)
[Discussion list after Test discussion with 1 reply](https://i.imgur.com/VbP7Hch.png)
[Discussion list after Test discussion with 2 replies](https://i.imgur.com/ZZtlr0y.png)

**Other Screenshots**
[Unapproved Test 2 discussion with 1 reply by same user](https://i.imgur.com/biFRXFv.png)
[Discussion list after Test 2 discussion with 1 reply by same user](https://i.imgur.com/k3feEqJ.png) (demonstrates that problem occurs regardless of user)
[Normal Test 3 discussion with 1 reply](https://i.imgur.com/RZsAGqE.png)
[Normal discussion list after Test 3 discussion with 1 reply](https://i.imgur.com/oY0q4rO.png) (demonstrates that no unexpected behavior occurs, this is not a widespread issue or regression)

**Environment**
- Flarum version: 0.1.0-beta.10
- Website URL: https://beta.flarum.site