Add gpg plugin to pom

Change-Id: I2e4bed805253f007cf311d977dcf0e082862cc7a
diff --git a/pom.xml b/pom.xml
index 4c9d352..74ae02a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -315,6 +315,20 @@
                     </execution>
                 </executions>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-gpg-plugin</artifactId>
+                <version>3.1.0</version>
+                <executions>
+                    <execution>
+                        <id>sign-artifacts</id>
+                        <phase>verify</phase>
+                        <goals>
+                            <goal>sign</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
         </plugins>
     </build>