build(deps): bump github.com/mrz1836/go-datastore from 0.5.14 to 0.5.21

Bumps [github.com/mrz1836/go-datastore](https://github.com/mrz1836/go-datastore) from 0.5.14 to 0.5.21.
- [Release notes](https://github.com/mrz1836/go-datastore/releases)
- [Changelog](https://github.com/mrz1836/go-datastore/blob/master/.goreleaser.yml)
- [Commits](mrz1836/go-datastore@v0.5.14...v0.5.21)

---
updated-dependencies:
- dependency-name: github.com/mrz1836/go-datastore
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>