Update backports.functools-lru-cache to 1.5

[pyup-bot]

There's a new version of backports.functools-lru-cache available. You are currently using 1.4. I have updated it to 1.5

These links might come in handy: PyPI | Changelog | Repo

Changelog

1.5

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Refresh package metadata including publishing license with the wheel (11).

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖