Fix typo

[q0w]

What do these changes do?

Fix ci fails like this
https://github.com/aio-libs/yarl/runs/5186918297?check_suite_focus=true

Are there changes in behavior for the user?

Related issue number

Checklist

• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes
• Add a new news fragment into the CHANGES folder
  • name it <issue_id>.<type> (e.g. 588.bugfix)
  • if you don't have an issue_id change it to the pr id after creating the PR
  • ensure type is one of the following:
    • .feature: Signifying a new feature.
    • .bugfix: Signifying a bug fix.
    • .doc: Signifying a documentation improvement.
    • .removal: Signifying a deprecation or removal of public API.
    • .misc: A ticket has been closed, but it is not of interest to users.
  • Make sure to use full sentences with correct case and punctuation, for example: Fix issue with non-ascii contents in doctest text files.

[mjpieters]

This does not, actually, fix the yarl issue; the typo is unfortunate but as yarl uses the default value it doesn't actually matter here.

The actual problem is that get-releasenote doesn't handle multi-line version files, for which I created aio-libs/get-releasenote#36.