b67a93a487
Commit 741e9cc61e was missing this.
Leads to annoying errors such as
```
$ bundle
Your Gemfile lists the gem minitest-parallel_fork (>= 0) more than once.
You should probably keep only one of them.
Remove any duplicate entries and specify the gem only once.
While it's not a problem now, it could cause errors if you change the version of one of them later.
```
586 B
586 B