Re-enabling typescript node test

Created by: osharav

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Description of the PR

As requested in: #1138 (closed) trying to fix issue with typescript compiler for typescript-node test. This seems to be a result of a change in the https://github.com/DefinitelyTyped/DefinitelyTyped repo. They have deprecated the ClientResponse interface in node 10. To resolve (at least until the generator uses the new IncomingMessage interface), I've specifically used the type definitions for node 8 in the relevant package.mustache file. I've ran the sample, installed node_modules and then confirmed that I can run tsc and see the compiled JavaScript.

Regards, Omer.