chore: enforce file extensions on imports (#6202)

* chore: enforce file extensions on imports

To make our output agnostic it should include file extensions in the
output, as per the ESM spec. It's a bit odd for Node packages but makes
it easier to publish a browser build.

scripts/ensure-correct-devtools-protocol-package.ts

@@ -33,6 +33,7 @@
  * find the one closest to our Chromium revision.
  */
 
+// eslint-disable-next-line import/extensions
 import { PUPPETEER_REVISIONS } from '../src/revisions';
 import { execSync } from 'child_process';