Update index.md.njk

Correction in research section to clarify it was the design not the component that was originally tested by GDS.

src/components/accordion/index.md.njk

@@ -79,7 +79,7 @@ Disabling controls is normally confusing for users. If there is no content for a
 
 This component is experimental because there are different approaches to accordions in services. More research is needed to determine the best approach, or to know when a different approach works better.
 
-This component was originally created and tested by a team at the Government Digital Service (GDS) on the [GOV.UK Service Manual](https://www.gov.uk/service-manual) and [GOV.UK topic pages](https://designnotes.blog.gov.uk/2017/06/29/designing-new-navigation-elements-for-gov-uk/).
+The design for this component was originally created and tested by a team at the Government Digital Service (GDS) on the [GOV.UK Service Manual](https://www.gov.uk/service-manual) and [GOV.UK topic pages](https://designnotes.blog.gov.uk/2017/06/29/designing-new-navigation-elements-for-gov-uk/).
 
 The team made sure the component is accessible, for example that users can interact with it using just the keyboard.