[Tests] `prefer-default-export`: fix test case
[Tests] `prefer-default-export`: fix test case

See https://github.com/benmosher/eslint-plugin-import/commit/e6f601812c2b30531beb7f5155c2e0a774db8ee4#r45298298

benmosher/eslint-plugin-import,benmosher/eslint-plugin-import,benmosher/eslint-plugin-import