Fix json schema type name for boolean.

Was boolean should have been bool.

Closes: #4196

Author: gongxuanzhang

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/schema/JsonSchemaObject.java

@@ -295,7 +295,7 @@ interface Type {
 		Type OBJECT = jsonTypeOf("object");
 		Type ARRAY = jsonTypeOf("array");
 		Type NUMBER = jsonTypeOf("number");
-		Type BOOLEAN = jsonTypeOf("boolean");
+		Type BOOLEAN = jsonTypeOf("bool");
 		Type STRING = jsonTypeOf("string");
 		Type NULL = jsonTypeOf("null");