Clarify instructions in Step 7

[Calorion]

Feature Request

Describe the problem/friction you are trying to solve
Step 7: Respond to a review says,

Click the Files Changed tab in this pull request
Edit your newly added file
Replace line 5 with something new

But it’s not at all clear to a new user just how to edit the file. There’s no obvious “edit” button (except to edit the title). Eventually I discovered that the “Edit file” command was under the “…” button.

Describe your ideal solution
Include a description of how to enter Edit mode after Step 1.