Update helmet.md

Author: Mick Lawitzke

content/security/helmet.md

@@ -17,7 +17,7 @@ Once the installation is complete, apply it as a global middleware.
 ```typescript
 import * as helmet from 'helmet';
 // somewhere in your initialization file
-await app.use(helmet());
+app.use(helmet());
 ```
 
 > info **Hint** If you are getting the `This expression is not callable` error while trying to import `Helmet`, you very likely have the `allowSyntheticDefaultImports` and `esModuleInterop` options set to `true` in your project's `tsconfig.json` file. If that's the case, change the import statement to: `import helmet from 'helmet'` instead.