Bump redis-collections from 0.8.1 to 0.9.1 (#38)

Bumps [redis-collections](https://github.com/redis-collections/redis-collections) from 0.8.1 to 0.9.1.
- [Release notes](https://github.com/redis-collections/redis-collections/releases)
- [Changelog](https://github.com/redis-collections/redis-collections/blob/master/docs/changelog.rst)
- [Commits](redis-collections/redis-collections@v0.8.1...v0.9.1)

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>