fix bug: change sql-query in localArtifactRepository (#820)

Also-by: Nazife Basbaz <nazife.basbaz@bosch-si.com>
Signed-off-by: Ahmed Sayed <ahmed.sayed@bosch-si.com>

hawkbit-core/src/main/java/org/eclipse/hawkbit/api/ApiType.java

@@ -22,5 +22,5 @@ public enum ApiType {
     /**
      * Support for Direct Device Integration API.
      */
-    DDI;
+    DDI
 }

hawkbit-core/src/main/java/org/eclipse/hawkbit/artifact/repository/ArtifactRepository.java

@@ -84,4 +84,16 @@ public interface ArtifactRepository {
      *            to erase
      */
     void deleteByTenant(@NotEmpty String tenant);
+
+    /**
+     * Checks if an artifact exists for a given tenant by its sha1 hash
+     *
+     * @param tenant
+     *            the tenant
+     * @param sha1Hash
+     *            the sha1-hash of the file to lookup.
+     *
+     * @return the boolean whether the atrifact exists or not
+     */
+    boolean existsByTenantAndSha1(@NotEmpty String tenant, @NotEmpty String sha1Hash);
 }