tsconfig.json does not restrict DOM types

[RA80533]

The lib compiler option is used to tell the TypeScript compiler which APIs will be available at runtime in the environment that will execute the transpired code. By default, lib will include type definitions for the DOM in addition to APIs corresponding to whatever level ECMAScript the target environment is expected to be (sourced from the target property).

The project tsconfig.json file should be updated with its lib property configured to whatever ECMAScript version is being targeted in order to override the default inclusion of DOM APIs.