Docs: clarify "Via JavaScript" usage example for Accordion Collapse (#41501)

Author: louismaximepiton

site/src/content/docs/components/accordion.mdx

@@ -179,7 +179,7 @@ To add accordion group management to a collapsible area, add the data attribute
 Enable manually with:
 
 ```js
-const accordionCollapseElementList = document.querySelectorAll('#myAccordion.collapse')
+const accordionCollapseElementList = document.querySelectorAll('#myAccordion .collapse')
 const accordionCollapseList = [...accordionCollapseElementList].map(accordionCollapseEl => new bootstrap.Collapse(accordionCollapseEl))
 ```