Reports if namespace import is used.
Valid:
import defaultExport from './foo'
import { a, b } from './bar'
import defaultExport, { a, b } from './foobar'
...whereas here imports will be reported:
import * as foo from 'foo';
import defaultExport, * as foo from 'foo';
If you want to use namespaces, you don't want to use this rule.