Fix GPG plugin (#3585)

Fixes https://github.com/Activiti/Activiti/issues/3584

pom.xml

@@ -768,6 +768,12 @@ limitations under the License.
                 <goals>
                   <goal>sign</goal>
                 </goals>
+                <configuration>
+                  <gpgArguments>
+                    <arg>--pinentry-mode</arg>
+                    <arg>loopback</arg>
+                  </gpgArguments>
+                </configuration>
               </execution>
             </executions>
           </plugin>