add maven-javadoc-plugin to the build pluginManagement to avoid a warning that this might 'threaten' the stability of the build

Author: TheSnoozer

pom.xml

@@ -129,6 +129,10 @@
                     <artifactId>maven-site-plugin</artifactId>
                     <version>3.9.1</version>
                 </plugin>
+                <plugin>
+                    <artifactId>maven-javadoc-plugin</artifactId>
+                    <version>3.2.0</version>
+                </plugin>
             </plugins>
         </pluginManagement>