Request: Allow for separate comment when all dependencies met

[houserx-jmcc]

I'm currently using a template like this:

---

Warning
Pull request will not be mergeable until its dependencies are resolved.

Dependencies:

• yada yada
• this that

---

and it would be nice to be able to show something different once all the dependencies were to make sure its clear the comment & check are in sync:

---

✅ All dependencies have been satisfied 🎉

Dependencies:

• yada yada
• this that

---

So being able to specify a 'success' comment would be great!