[Security] Bump debug from 2.6.8 to 2.6.9

Bumps [debug](https://github.com/visionmedia/debug) from 2.6.8 to 2.6.9. **This update includes a security fix.**
- [Release notes](https://github.com/visionmedia/debug/releases)
- [Changelog](https://github.com/visionmedia/debug/blob/2.6.9/CHANGELOG.md)
- [Commits](debug-js/debug@2.6.8...2.6.9)

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

yarn.lock

@@ -1123,8 +1123,8 @@ date-now@^0.1.4:
   resolved "https://registry.yarnpkg.com/date-now/-/date-now-0.1.4.tgz#eaf439fd4d4848ad74e5cc7dbef200672b9e345b"
 
 debug@^2.2.0, debug@^2.6.3, debug@^2.6.8:
-  version "2.6.8"
-  resolved "https://registry.yarnpkg.com/debug/-/debug-2.6.8.tgz#e731531ca2ede27d188222427da17821d68ff4fc"
+  version "2.6.9"
+  resolved "https://registry.yarnpkg.com/debug/-/debug-2.6.9.tgz#5d128515df134ff327e90a4c93f4e077a536341f"
   dependencies:
     ms "2.0.0"