Add missing version definition for the cleaning plugin

Issue-Ref: 3620
Issue-Url: https://af3-developer.fortiss.org/issues/3620


Signed-off-by: Alexander Diewald <diewald@fortiss.org>

releng/org.fortiss.af3.configuration/pom.xml

@@ -107,6 +107,11 @@
 
     <pluginManagement>
       <plugins>
+        <plugin>
+          <groupId>org.apache.maven.plugins</groupId>
+          <artifactId>maven-clean-plugin</artifactId>
+          <version>3.1.0</version>
+        </plugin>
         <plugin>
           <groupId>org.eclipse.tycho</groupId>
           <artifactId>tycho-surefire-plugin</artifactId>