Update dependency furo to v2023.8.19

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
furo	2023.7.26 -> 2023.8.19

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Release Notes

pradyunsg/furo (furo)

### [`v2023.8.19`](https://togithub.com/pradyunsg/furo/compare/2023.08.17...2023.08.19) [Compare Source](https://togithub.com/pradyunsg/furo/compare/2023.08.17...2023.08.19) ### [`v2023.8.17`](https://togithub.com/pradyunsg/furo/compare/2023.07.26...2023.08.17) [Compare Source](https://togithub.com/pradyunsg/furo/compare/2023.07.26...2023.08.17)

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Configuration

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