Replace usage of deprecated Jackson constant

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## Unreleased
+
+* removed usage of deprecated Jackson constant, replaced with the recommended alternative
+
 ## 1.11.1
 
 * small updated to http client connection settings

pom.xml

@@ -26,7 +26,7 @@
         <postmark.version>1.11.1</postmark.version>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <java.version>1.8</java.version>
-        <jackson.minimum.version>2.9.7</jackson.minimum.version>
+        <jackson.minimum.version>2.12</jackson.minimum.version>
         <jackson.version>2.14.1</jackson.version>
         <junit.jupiter.version>5.8.2</junit.jupiter.version>
         <junit.platform.version>1.3.2</junit.platform.version>

src/main/java/com/postmarkapp/postmark/client/data/parser/DataHandler.java

@@ -17,7 +17,7 @@ public class DataHandler {
     public DataHandler() {
         this.mapper = new ObjectMapper();
         this.mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
-        this.mapper.setPropertyNamingStrategy(PropertyNamingStrategy.UPPER_CAMEL_CASE);
+        this.mapper.setPropertyNamingStrategy(PropertyNamingStrategies.UPPER_CAMEL_CASE);
         setLiberalMapper();
     }