Fix duplicate execution of the promote validations

  Seems we did not remove duplicate for verify store keys, which may
include duplicates. For example if target store and "availableInStores"
parameters are same.

Author: ligangty

addons/promote/common/src/main/java/org/commonjava/indy/promote/validate/PromotionValidationTools.java

@@ -168,7 +168,7 @@ public StoreKey[] getValidationStoreKeys( final ValidationRequest request, final
         Logger logger = LoggerFactory.getLogger( getClass() );
         logger.debug( "Got extra validation keys string: '{}'", verifyStores );
 
-        List<StoreKey> verifyStoreKeys = new ArrayList<>();
+        Set<StoreKey> verifyStoreKeys = new HashSet<>();
         if ( includeSource )
         {
             verifyStoreKeys.add( request.getSourceRepository().getKey() );
@@ -204,7 +204,7 @@ public StoreKey[] getValidationStoreKeys( final ValidationRequest request, final
 
         logger.debug( "Using validation StoreKeys: {}", verifyStoreKeys );
 
-        return verifyStoreKeys.toArray( new StoreKey[verifyStoreKeys.size()] );
+        return verifyStoreKeys.toArray( new StoreKey[0] );
     }
 
     public String toArtifactPath( final ProjectVersionRef ref )
@@ -676,19 +676,19 @@ private void waitForCompletion( CountDownLatch latch )
     public <T> void forEach( Collection<T> collection, Closure closure )
     {
         logger.trace( "Exe on collection {} with closure {}", collection, closure );
-        collection.forEach( e -> closure.call( e ) );
+        collection.forEach( closure::call );
     }
 
     public <T> void forEach( T[] array, Closure closure )
     {
         logger.trace( "Exe on array {} with closure {}", array, closure );
-        Arrays.asList( array ).forEach( e -> closure.call( e ) );
+        Arrays.asList( array ).forEach( closure::call );
     }
 
     public <K, V> void forEach( Map<K, V> map, Closure closure )
     {
         Set<Map.Entry<K, V>> entries = map.entrySet();
         logger.trace( "Exe on map {} with closure {}", entries, closure );
-        entries.forEach( e -> closure.call( e ) );
+        entries.forEach( closure::call );
     }
 }