Bump sphinxext-opengraph from 0.7.5 to 0.8.2

Bumps [sphinxext-opengraph](https://github.com/wpilibsuite/sphinxext-opengraph) from 0.7.5 to 0.8.2.
- [Release notes](https://github.com/wpilibsuite/sphinxext-opengraph/releases)
- [Commits](wpilibsuite/sphinxext-opengraph@v0.7.5...v0.8.2)

---
updated-dependencies:
- dependency-name: sphinxext-opengraph
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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