Fix crash of lint rule no-document-import-in-page (#28148)

Fixes #28030 
Fixes #28169

## Bug

- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
- [x] Errors have helpful link attached, see `contributing.md`

packages/eslint-plugin-next/lib/rules/no-document-import-in-page.js

@@ -16,9 +16,11 @@ module.exports = {
         }
 
         const page = context.getFilename().split('pages')[1]
+        if (!page) {
+          return
+        }
         const { name, dir } = path.parse(page)
         if (
-          !page ||
           name.startsWith('_document') ||
           (dir === '/_document' && name === 'index')
         ) {

test/eslint-plugin-next/no-document-import-in-page.unit.test.js

@@ -86,6 +86,13 @@ ruleTester.run('no-document-import-in-page', rule, {
     `,
       filename: 'pages/_document/index.tsx',
     },
+    {
+      code: `import Document from "next/document"
+
+      export const Test = () => <p>Test</p>
+      `,
+      filename: 'components/test.js',
+    },
   ],
   invalid: [
     {