Update support boot versions in getting started doc

Author: markpollack

spring-ai-docs/src/main/antora/modules/ROOT/pages/getting-started.adoc

@@ -5,7 +5,7 @@ This section offers jumping off points for how to get started using Spring AI.
 
 You should follow the steps in each of the following sections according to your needs.
 
-NOTE: Spring AI supports Spring Boot 3.2.x and 3.3.x
+NOTE: Spring AI supports Spring Boot 3.4.x.  When Spring Boot 3.5.x is released, we will support that as well.
 
 [[spring-initializr]]
 == Spring Initializr