exclude the data-grid package from the imports rule

Signed-off-by: Fredrik Adelöw <freben@gmail.com>

packages/eslint-plugin/src/no-top-level-material-ui-4-imports.test.ts

@@ -47,6 +47,9 @@ ruleTester.run('path-imports-rule', rule, {
     {
       code: `import { CreateCSSProperties, StyledComponentProps } from '@material-ui/core/styles/withStyles';`,
     },
+    {
+      code: `import { DataGrid, GridColDef, GridValueGetterParams } from '@material-ui/data-grid';`,
+    },
   ],
   invalid: [
     {