Update to Jackson 2.9.9

https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.9.9

Notably, this includes a fix for CVE-2019-12086. See
FasterXML/jackson-databind#2326 for details.

Author: jvz

pom.xml

@@ -72,7 +72,7 @@
     <changelist>-SNAPSHOT</changelist>
     <java.level>8</java.level>
     <jenkins.version>2.60.3</jenkins.version>
-    <jackson.version>2.9.8</jackson.version>
+    <jackson.version>2.9.9</jackson.version>
   </properties>
 
   <repositories>