## Summary
This PR updates the Renovate config to account for the
`requirements*.txt` files in `docs/` directory.
The `mkdocs-material` upgrade is ignored because we use commit SHA for
the insider version and it should match the corresponding public version
as per the docs:
https://squidfunk.github.io/mkdocs-material/insiders/upgrade/
(`9.x.x-insiders-4.x.x`).
## Test Plan
```console
❯ renovate-config-validator
(node:83193) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
(Use `node --trace-deprecation ...` to show where the warning was created)
INFO: Validating .github/renovate.json5
INFO: Config validated successfully
```
