Upgrades to Struts 2.5.22
diff --git a/pom.xml b/pom.xml
index 8f78d78..407999d 100644
--- a/pom.xml
+++ b/pom.xml
@@ -40,7 +40,7 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <struts2.version>2.5.20</struts2.version>
+        <struts2.version>2.5.22</struts2.version>
         <log4j2.version>2.12.1</log4j2.version>
         <jetty-plugin.version>9.4.22.v20191022</jetty-plugin.version>
     </properties>