According to https://dev.mysql.com/doc/refman/5.7/en/update.html,
"You cannot update a table and select from the same table in a subquery."
Attempting to do so results in the error:

```
Mysql2::Error: Table 'issues' is specified twice, both as a target for 'UPDATE' and as a separate source for data
```

Instead, we can use a LEFT JOIN on the same table to make MySQL do the right
thing.

Closes #41498