docs: add missing operator quick start guide

Signed-off-by: Max Xu <[email protected]>

Author: maxsxu

docs/book/src/SUMMARY_PREFIX.md

@@ -1,7 +1,8 @@
 # Summary
 
 - [Introduction](./introduction.md)
-- [Getting Started](getting-started.md)
+- [Quick Start](quick-start.md)
+- [Quick Start Operator](quick-start-operator.md)
 - [AMIs](./topics/images/amis.md)
   - [Published AMIs](./topics/images/built-amis.md)
   - [Custom AMIs](./topics/images/custom-amis.md)