chore(deps): bump aws-sdk from 2.399.0 to 2.400.0

Bumps [aws-sdk](https://github.com/aws/aws-sdk-js) from 2.399.0 to 2.400.0.
- [Release notes](https://github.com/aws/aws-sdk-js/releases)
- [Changelog](https://github.com/aws/aws-sdk-js/blob/master/CHANGELOG.md)
- [Commits](aws/aws-sdk-js@v2.399.0...v2.400.0)

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

package.json

@@ -22,7 +22,7 @@
     "node": "8.10"
   },
   "dependencies": {
-    "aws-sdk": "^2.327.0",
+    "aws-sdk": "^2.400.0",
     "ims-lti": "^3.0.2",
     "jsonwebtoken": "^8.1.0",
     "md5": "^2.2.1",