Adding a TypeScript CloudFront Function Example

[gilaniasher]

Summary

This PR adds a new CloudFront Functions example which demonstrates how to use TypeScript to validate query parameters. The included Webpack config produces a JavaScript file which can be uploaded directly to CloudFront Functions.

The example here also supports unit testing with Jest.

Testing

• I verified that the code correctly builds when using npm run build and tests pass when running npm run test
• I uploaded the built JavaScript code from this example to the CloudFront Function console and verified that it works as expected

Successful Request - Lowercase Query Params are Considered Valid

Failed Request - Uppercase Query Params are Considered Invalid

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