chore: fix TypeError (#198)

replace npm run test:update with npm run test

Co-authored-by: Kent C. Dodds <[email protected]>

Author: priyang12

CONTRIBUTING.md

@@ -29,8 +29,8 @@ series [How to Contribute to an Open Source Project on GitHub][egghead]
 ## Committing and Pushing changes
 
 Please make sure to run the tests before you commit your changes. You can run
-`npm run test:update` which will update any snapshots that need updating. Make
-sure to include those changes (if they exist) in your commit.
+`npm run test` which will update any snapshots that need updating. Make sure to
+include those changes (if they exist) in your commit.
 
 ## Help needed
 

src/types.d.ts

@@ -204,4 +204,4 @@ type MDXExportFunction<
 > = (
   code: string,
   globals?: Record<string, unknown>,
-) => MDXExport<ExportedObject, Frontmatter>
+) => ReturnType<MDXExport<ExportedObject, Frontmatter>>