This fixes an issue bundling es2015 with ng_rollup_bundle that was covered up by a typo when refactoring ng_rollup_bundle to not use legacy rollup_bundle internals and to use the new terser_minified rule and npm_package_bin to call brotli.
Note: ng_rollup_bundle is only used in the angular repo and not externally so this issue does not affect users
PR Close#33808