Add missing documentation for get_application_context

[jgayfer]

Summary

We missed adding docs for one of this function's parameters.

Checklist

• If code changes were made then they have been tested.
  • I have updated the documentation to reflect the changes.
• This PR fixes an issue.
• This PR adds something new (e.g. new method or parameters).
• This PR is a breaking change (e.g. methods or parameters removed/renamed)
• This PR is not a code change (e.g. documentation, README, ...)

[CodeWithSwastik]

Could you change the base branch of this PR to slash?

[jgayfer]

@CodeWithSwastik Not really. The method get_application_context is already in master, which is what this PR is adding docs for.

[jgayfer]

Oh it's up to date, I probably can 👍

[CodeWithSwastik]

Thanks, we're adding changes to slash before merging them to master.