Bump postcss-cli from 8.3.1 to 9.0.0 (open-telemetry#785)

Bumps [postcss-cli](https://github.com/postcss/postcss-cli) from 8.3.1 to 9.0.0.
- [Release notes](https://github.com/postcss/postcss-cli/releases)
- [Changelog](https://github.com/postcss/postcss-cli/blob/master/CHANGELOG.md)
- [Commits](postcss/postcss-cli@8.3.1...9.0.0)

---
updated-dependencies:
- dependency-name: postcss-cli
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

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

Author: dependabot[bot]

package.json

@@ -27,7 +27,7 @@
     "esm": "^3.2.25",
     "node-fetch": "^2.6.1",
     "postcss": "^8.3.6",
-    "postcss-cli": "^8.3.1",
+    "postcss-cli": "^9.0.0",
     "yaml": "^1.10.2"
   },
   "dependencies": {