[Security] Bump debug from 2.6.8 to 2.6.9 (#81)

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

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

yarn.lock

@@ -265,18 +265,12 @@ core-util-is@~1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/core-util-is/-/core-util-is-1.0.2.tgz#b5fd54220aa2bc5ab57aab7140c940754503c1a7"
 
-debug@^2.1.2, debug@^2.3.3:
+debug@^2.1.2, debug@^2.2.0, debug@^2.3.3:
   version "2.6.9"
   resolved "https://registry.yarnpkg.com/debug/-/debug-2.6.9.tgz#5d128515df134ff327e90a4c93f4e077a536341f"
   dependencies:
     ms "2.0.0"
 
-debug@^2.2.0:
-  version "2.6.8"
-  resolved "https://registry.yarnpkg.com/debug/-/debug-2.6.8.tgz#e731531ca2ede27d188222427da17821d68ff4fc"
-  dependencies:
-    ms "2.0.0"
-
 debug@^3.1.0:
   version "3.2.6"
   resolved "https://registry.yarnpkg.com/debug/-/debug-3.2.6.tgz#e83d17de16d8a7efb7717edbe5fb10135eee629b"