Update cypress-studio.mdx (#6139)

reflect limitation expressed in cypress-io/cypress#26146

Author: bjuergens

docs/app/guides/cypress-studio.mdx

@@ -46,6 +46,7 @@ attribute to your Cypress configuration.
   yet work with Component Testing.
 - Cypress Studio does not support writing tests that use domains of [multiple
   origins](/app/guides/cross-origin-testing).
+- Cypress Studio can not interact with elements within a ShadowDom directly, though it can still run tests that do.
 
 ## Overview