Fix message list message item height

How to see the screen:
- Create a user with an email of either "handle2@test", "handle3@test", or "handle4@test" (this adds messages to the account)
- Click the upload button (this will load new messages)
- Click messages button on dashboard
- Click on the user you created (it should have a red icon on it)
- You will now see the UI showing the list of messages for that user

You'll notice a lot of extra space at the bottom. We need to make the height of these grid items the same as the height of the grid items in the user select screen that came right before it.

The screen that needs to be fixed is "IndividualMessageListScreen"

Reproduce the issue using the listed account emails and navigation steps, then inspect the IndividualMessageListScreen alongside the preceding user select screen. Compare the message grid item heights and confirm that the extra bottom space is gone while the messages remain usable.

Written by the indexing model from the issue text.