Fix typo in object-mapping.adoc.

Closes spring-projects#3076

Author: theHacker

src/main/antora/modules/ROOT/pages/object-mapping.adoc

@@ -299,7 +299,7 @@ Spring Data automatically tries to detect a persistent entity's constructor to b
 The resolution algorithm works as follows:
 
 1. If there is a constructor that is annotated with `@PersistenceCreator`, it is used.
-2. If the type is a <<mapping.kotlin,Kotlin data cass>> the primary constructor is used.
+2. If the type is a <<mapping.kotlin,Kotlin data class>> the primary constructor is used.
 3. If there is a single static factory method annotated with `@PersistenceCreator` then it is used.
 4. If there is a single constructor, it is used.
 5. If there are multiple constructors and exactly one is annotated with `@PersistenceCreator`, it is used.