Update vendor/composure

[gaelicWizard]

Description

Update "composure" from "https://github.com/erichs/composure@master"
git-vendor-name: composure
git-vendor-dir: vendor/github.com/erichs/composure
git-vendor-repository: https://github.com/erichs/composure
git-vendor-ref: master

Motivation and Context

I made git vendor work! I think the key to me figuring out something stupid is asking for help. As soon as I do, my brain immediately figures out what I was doing wrong. 🙃
This closes #2026...

How Has This Been Tested?

Testing? Where we're going, we don't need testing!

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code follows the code style of this project.
• If my change requires a change to the documentation, I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• If I have added a new file, I also added it to clean_files.txt and formatted it using lint_clean_files.sh.
• I have added tests to cover my changes, and all the new and existing tests pass.

[NoahGorny]

Well done @gaelicWizard !