Fix typo

See gh-23215

spring-boot-project/spring-boot-docs/src/docs/asciidoc/spring-boot-features.adoc

@@ -450,7 +450,7 @@ the beans lifecycle or even processing application events.
 With {spring-framework-api}/core/metrics/ApplicationStartup.html[ApplicationStartup`], Spring Framework  {spring-framework-docs}/core.html#context-functionality-startup[allows you track the application startup sequence with `StartupStep`s].
 This data can be collected for profiling purposes, or just to have a better understanding of an application startup process.
 
-You can choose a `ApplicationStartup` implementation when setting up the `SpringApplication` instance.
+You can choose an `ApplicationStartup` implementation when setting up the `SpringApplication` instance.
 For example, to use the `BufferingApplicationStartup`, you could write:
 
 [source,java,indent=0]