Bump async from 3.2.0 to 3.2.2 in /docs

Bumps [async](https://github.com/caolan/async) from 3.2.0 to 3.2.2.
- [Release notes](https://github.com/caolan/async/releases)
- [Changelog](https://github.com/caolan/async/blob/master/CHANGELOG.md)
- [Commits](https://github.com/caolan/async/compare/v3.2.0...v3.2.2)

---
updated-dependencies:
- dependency-name: async
  dependency-type: direct:production
...

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

docs/yarn.lock

@@ -1880,9 +1880,9 @@ async@^2.6.2:
     lodash "^4.17.14"
 
 async@^3.2.0:
-  version "3.2.0"
+  version "3.2.2"
-  resolved "https://registry.yarnpkg.com/async/-/async-3.2.0.tgz#b3a2685c5ebb641d3de02d161002c60fc9f85720"
+  resolved "https://registry.yarnpkg.com/async/-/async-3.2.2.tgz#2eb7671034bb2194d45d30e31e24ec7e7f9670cd"
-  integrity sha512-TR2mEZFVOj2pLStYxLht7TyfuRzaydfpxr3k9RpHIzMgw7A64dzsdqCxH1WJyQdoe8T10nDXd9wnEigmiuHIZw==
+  integrity sha512-H0E+qZaDEfx/FY4t7iLRv1W2fFI6+pyCeTw1uN20AQPiwqwM6ojPxHxdLv4z8hi2DtnW9BOckSspLucW7pIE5g==
 
 asynckit@^0.4.0:
   version "0.4.0"