Run checks on verify phase

- Changed the phase to run checkstyle, findbug, pmd(not enabled yet) chesks to 'verify' phase.

Notes:
- "$ mvn verify" will compile test and run above checks and fails the build on check failure.
- According to default maven lifecycle definition
   https://maven.apache.org/guides/introduction/introduction-to-the-lifecycle.html#Lifecycle_Reference
  'verify' phase is defined as a phase to check quality criteria.

Change-Id: I3583ec1df1ea631cc6e671482e4898ee538570ba
diff --git a/pom.xml b/pom.xml
index 8c21242..ad490ea 100644
--- a/pom.xml
+++ b/pom.xml
@@ -56,7 +56,7 @@
         <executions>
           <execution>
             <id>validate-checkstyle</id>
-            <phase>compile</phase>
+            <phase>verify</phase>
             <goals>
               <goal>check</goal>
             </goals>
@@ -274,10 +274,9 @@
         <executions>
           <execution>
             <id>validate-findbugs</id>
-            <phase>compile</phase>
+            <phase>verify</phase>
             <goals>
-              <!--  Uncomment this goal to make the build fail on findbugs errors -->
-              <!--<goal>check</goal>-->
+              <goal>check</goal>
             </goals>
           </execution>
         </executions>
@@ -307,7 +306,7 @@
         <executions>
           <execution>
             <id>validate-pmd</id>
-            <phase>compile</phase>
+            <phase>verify</phase>
             <goals>
               <!--  Uncomment this goal to make the build fail on pmd errors -->
               <!--<goal>check</goal>-->