Update coldstartups.adoc (#2290)

Typo fix

Author: klakpin

src/main/docs/guide/lambda/coldstartups.adoc

@@ -8,4 +8,4 @@ During the initialization phase:
 - AWS Lambda starts a JVM.
 - Java runtime loads and initializes handler class.
 
-The intialization phase has access to more CPU, because of that Micronaut starts the application context and eagerly inits singletons during the intialization of the handler class.
+The initialization phase has access to more CPU, because of that Micronaut starts the application context and eagerly inits singletons during the intialization of the handler class.