Provide external modules to plugins

Summary: esbuild references external modules via `require`. We wrap `require` to point the references to built-in modules to global variables

Reviewed By: lblasa

Differential Revision: D39311893

fbshipit-source-id: a99480161c082f4095d78c22271f114532f32c16

desktop/flipper-common/src/index.tsx

@@ -23,6 +23,7 @@ export {
 export * from './server-types';
 export * from './companion-types';
 export * from './ServerAddOn';
+export * from './plugin-external-modules';
 export {sleep} from './utils/sleep';
 export {timeout} from './utils/timeout';
 export {isTest} from './utils/isTest';