Fix typo on tutorial.rst (#5893)

docs/intro/tutorial.rst

@@ -309,7 +309,7 @@ the :meth:`~scrapy.selector.SelectorList.re` method to extract using
 >>> response.css('title::text').re(r'(\w+) to (\w+)')
 ['Quotes', 'Scrape']
 
-In order to find the proper CSS selectors to use, you might find useful opening
+In order to find the proper CSS selectors to use, you might find it useful to open
 the response page from the shell in your web browser using ``view(response)``.
 You can use your browser's developer tools to inspect the HTML and come up
 with a selector (see :ref:`topics-developer-tools`).