[java][api] Use AnnotationIntrospectorPair over deprecated class

* One-line fix
* Similar to Issue cloudera#35 and PR cloudera#49, but without the changes
to the Jackson dependency itself

Author: matthew-dailey

java/src/main/java/com/cloudera/api/ApiObjectMapper.java

@@ -16,10 +16,10 @@
 
 package com.cloudera.api;
 
-import com.fasterxml.jackson.databind.AnnotationIntrospector;
 import com.fasterxml.jackson.databind.MapperFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationFeature;
+import com.fasterxml.jackson.databind.introspect.AnnotationIntrospectorPair;
 import com.fasterxml.jackson.module.jaxb.JaxbAnnotationIntrospector;
 
 import java.text.DateFormat;
@@ -38,7 +38,7 @@ public ApiObjectMapper() {
 
     // Allow JAX-B annotations.
     setAnnotationIntrospector(
-        new AnnotationIntrospector.Pair(
+        new AnnotationIntrospectorPair(
             getSerializationConfig().getAnnotationIntrospector(),
             new JaxbAnnotationIntrospector()));