Update dependency org.apache.maven.plugins:maven-clean-plugin to v2.6.1 (#2)

Author: gliptak

pom.xml

@@ -26,7 +26,7 @@
     <skip.central.release>false</skip.central.release>
     <gpg.useagent>true</gpg.useagent>
 
-    <plugin.version.clean>2.6</plugin.version.clean>
+    <plugin.version.clean>2.6.1</plugin.version.clean>
     <plugin.version.source>3.3.1</plugin.version.source>
     <plugin.version.compiler>3.14.0</plugin.version.compiler>
     <plugin.version.jar>2.5</plugin.version.jar>