GH-5302 Add Update SPARQL Query Debug Log

Author: odysa

tools/server-spring/src/main/java/org/eclipse/rdf4j/http/server/repository/statements/StatementsController.java

@@ -156,6 +156,11 @@ private ModelAndView getSparqlUpdateResult(Repository repository, HttpServletReq
 			throw new ClientHTTPException("Updates must be non-empty");
 		}
 
+		if (logger.isDebugEnabled()) {
+			final int queryHashCode = sparqlUpdateString.hashCode();
+			logger.debug("update query {} = {}", queryHashCode, sparqlUpdateString);
+		}
+
 		// default query language is SPARQL
 		QueryLanguage queryLn = QueryLanguage.SPARQL;