Change callout type in end-to-end testing docs

Updated the callout from 'important' to 'note' to better reflect the informational nature of the message about generated test files.

Author: karangattu

docs/end-to-end-testing.qmd

@@ -189,7 +189,7 @@ pip install "shiny[test,testgen]"
   - Anthropic: `export ANTHROPIC_API_KEY=...`
   - OpenAI: `export OPENAI_API_KEY=...`
 
-::: callout-important
+::: callout-note
 The generated file is a **starting point**, not a full coverage suite. Iterate toward meaningful, stable assertions aligned with your app’s business logic.
 :::