chore(deps): bump github.com/stretchr/testify from 1.7.0 to 1.8.0 (#517)

Bumps [github.com/stretchr/testify](https://github.com/stretchr/testify) from 1.7.0 to 1.8.0.
- [Release notes](https://github.com/stretchr/testify/releases)
- [Commits](stretchr/testify@v1.7.0...v1.8.0)

---
updated-dependencies:
- dependency-name: github.com/stretchr/testify
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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