Bump github.com/stretchr/testify from 1.8.3 to 1.8.4 in /pkg/quantile (…

…#94)

* Bump github.com/stretchr/testify from 1.8.3 to 1.8.4 in /pkg/quantile

Bumps [github.com/stretchr/testify](https://github.com/stretchr/testify) from 1.8.3 to 1.8.4.
- [Release notes](https://github.com/stretchr/testify/releases)
- [Commits](stretchr/testify@v1.8.3...v1.8.4)

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

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

* make tidy

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Yang Song <yang.song@datadoghq.com>