Update dependency org.apache.maven.plugins:maven-war-plugin to v2.6

Author: renovate[bot]

pom.xml

@@ -37,7 +37,7 @@
     <plugin.version.deploy>3.1.4</plugin.version.deploy>
     <plugin.version.assembly>2.4.1</plugin.version.assembly>
     <plugin.version.ejb>2.4</plugin.version.ejb>
-    <plugin.version.war>2.4</plugin.version.war>
+    <plugin.version.war>2.6</plugin.version.war>
     <plugin.version.ear>2.9.1</plugin.version.ear>
     <plugin.version.rar>2.4</plugin.version.rar>
     <plugin.version.gpg>3.2.7</plugin.version.gpg>