updated maven build files

Change-Id: I33c69978fe7a22485a7fd5ceb7a480e84e8bcdb3

grpc/pom.xml

@@ -185,6 +185,12 @@
                         <goals>
                             <goal>sign</goal>
                         </goals>
+                        <configuration>
+                            <gpgArguments>
+                                <arg>--pinentry-mode</arg>
+                                <arg>loopback</arg>
+                            </gpgArguments>
+                        </configuration>
                     </execution>
                 </executions>
             </plugin>

pom.xml

@@ -110,7 +110,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-gpg-plugin</artifactId>
-        <version>1.5</version>
+        <version>1.6</version>
         <executions>
           <execution>
             <id>sign-artifacts</id>
@@ -118,6 +118,12 @@
             <goals>
               <goal>sign</goal>
             </goals>
+            <configuration>
+                <gpgArguments>
+                    <arg>--pinentry-mode</arg>
+                    <arg>loopback</arg>
+                </gpgArguments>
+            </configuration>
           </execution>
         </executions>
       </plugin>