template: pass empty checksum for template copy

Since checksum value stored for source template while copying is for the downloaded file and not the installed template, an empty value is passed to download service to prevent checsum mismatch.

Signed-off-by: Abhishek Kumar <abhishek.kumar@shapeblue.com>

Author: shwstppr

engine/storage/image/src/main/java/org/apache/cloudstack/storage/image/TemplateServiceImpl.java

@@ -1045,6 +1045,8 @@ public AsyncCallFuture<TemplateApiResult> copyTemplate(TemplateInfo srcTemplate,
         }
         tmplForCopy.setUrl(url);
 
+        tmplForCopy.getImage().setChecksum("");
+
         if (s_logger.isDebugEnabled()) {
             s_logger.debug("Mark template_store_ref entry as Creating");
         }