update README: docker requirement

AlexCheema · AlexCheema · commit 157281e53079 · 2020-04-04T14:26:04.000+02:00
diff --git a/packages/@aws-cdk/aws-lambda-nodejs/README.md b/packages/@aws-cdk/aws-lambda-nodejs/README.md
@@ -19,6 +19,8 @@
 
 This library provides constructs for Node.js Lambda functions.
 
+To use this module, you will need to have Docker installed.
+
 ### Node.js Function
 Define a `NodejsFunction`:
 
