docs(lambda-nodejs): Example for esbuild missing comma in property (a…

…ws#13520)

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Example under esbuild appears to be missing comma.

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packages/@aws-cdk/aws-lambda-nodejs/README.md

@@ -142,7 +142,7 @@ new lambda.NodejsFunction(this, 'my-handler', {
     },
     logLevel: LogLevel.SILENT, // defaults to LogLevel.WARNING
     keepNames: true, // defaults to false
-    tsconfig: 'custom-tsconfig.json' // use custom-tsconfig.json instead of default,
+    tsconfig: 'custom-tsconfig.json', // use custom-tsconfig.json instead of default,
     metafile: true, // include meta file, defaults to false
     banner : '/* comments */', // by default no comments are passed
     footer : '/* comments */', // by default no comments are passed