chore(deps): bump aws-sdk from 2.553.0 to 2.556.0 (#4675)

Bumps [aws-sdk](https://github.com/aws/aws-sdk-js) from 2.553.0 to 2.556.0.
- [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@v2.553.0...v2.556.0)

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

packages/@aws-cdk/aws-cloudfront/package.json

@@ -64,7 +64,7 @@
   "license": "Apache-2.0",
   "devDependencies": {
     "@aws-cdk/assert": "1.14.0",
-    "aws-sdk": "^2.553.0",
+    "aws-sdk": "^2.556.0",
     "cdk-build-tools": "file:../../../tools/cdk-build-tools",
     "cdk-integ-tools": "file:../../../tools/cdk-integ-tools",
     "cfn2ts": "file:../../../tools/cfn2ts",

packages/@aws-cdk/aws-cloudtrail/package.json

@@ -64,7 +64,7 @@
   "license": "Apache-2.0",
   "devDependencies": {
     "@aws-cdk/assert": "1.14.0",
-    "aws-sdk": "^2.553.0",
+    "aws-sdk": "^2.556.0",
     "cdk-build-tools": "file:../../../tools/cdk-build-tools",
     "cdk-integ-tools": "file:../../../tools/cdk-integ-tools",
     "cfn2ts": "file:../../../tools/cfn2ts",