Update estimateStatistics example response with location header

Author: manjarisenthil

api-reference/beta/api/security-ediscoverysearch-estimatestatistics.md

@@ -113,4 +113,5 @@ The following example shows the response.
 -->
 ``` http
 HTTP/1.1 204 No Content
+Location: https://graph.microsoft.com/beta/security/cases/ediscoverycases('4c551bc5-f6f8-435c-8391-d1a08f1ffd5b')/operations('698514cc118f4c8b8cdf1bf0797bf478')
 ```