feat(lambda-nodejs): allow jsx and tsx entry files (aws#8892)

Support JSX adn TSX for entry files

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

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

@@ -34,7 +34,7 @@ automatically transpiled and bundled whether it's written in JavaScript or TypeS
 Alternatively, an entry file and handler can be specified:
 ```ts
 new lambda.NodejsFunction(this, 'MyFunction', {
-  entry: '/path/to/my/file.ts',
+  entry: '/path/to/my/file.ts', // accepts .js, .jsx, .ts and .tsx files
   handler: 'myExportedFunc'
 });
 ```

packages/@aws-cdk/aws-lambda-nodejs/lib/function.ts

@@ -84,7 +84,7 @@ export class NodejsFunction extends lambda.Function {
  */
 function findEntry(id: string, entry?: string): string {
   if (entry) {
-    if (!/\.(js|ts)$/.test(entry)) {
+    if (!/\.(jsx?|tsx?)$/.test(entry)) {
       throw new Error('Only JavaScript or TypeScript entry files are supported.');
     }
     if (!fs.existsSync(entry)) {

packages/@aws-cdk/aws-lambda-nodejs/test/function.test.ts

@@ -1,6 +1,8 @@
 import '@aws-cdk/assert/jest';
 import { Runtime } from '@aws-cdk/aws-lambda';
 import { Stack } from '@aws-cdk/core';
+import * as fs from 'fs';
+import * as path from 'path';
 import { NodejsFunction } from '../lib';
 import { Bundling } from '../lib/bundling';
 
@@ -67,6 +69,18 @@ test('throws when entry is not js/ts', () => {
   })).toThrow(/Only JavaScript or TypeScript entry files are supported/);
 });
 
+test('accepts tsx', () => {
+  const entry = path.join(__dirname, 'handler.tsx');
+
+  fs.symlinkSync(path.join(__dirname, 'function.test.handler1.ts'), entry);
+
+  expect(() => new NodejsFunction(stack, 'Fn', {
+    entry,
+  })).not.toThrow();
+
+  fs.unlinkSync(entry);
+});
+
 test('throws when entry does not exist', () => {
   expect(() => new NodejsFunction(stack, 'Fn', {
     entry: 'notfound.ts',