Fixed failing BWC tests when listing views unexpectedly works

ES 8.x returns 405 because it sees _query/views as invalid GET _query

ResponseException: method [GET], host [http://[::1]:38479], URI [/_query/views], status line [HTTP/1.1 405 Method Not Allowed]

Author: craigtaverner

x-pack/plugin/esql/qa/testFixtures/src/main/java/org/elasticsearch/xpack/esql/CsvTestsDataLoader.java

@@ -653,7 +653,8 @@ private static boolean clusterHasViewSupport(RestClient client, Logger logger) t
         } catch (ResponseException e) {
             logger.info("View listing error: {}", e.getMessage());
             int code = e.getResponse().getStatusLine().getStatusCode();
-            if (code == 400 || code == 500) {
+            // Different versions of Elasticsearch return different codes when views are not supported
+            if (code == 400 || code == 500 || code == 405) {
                 return false;
             }
             throw e;
@@ -667,8 +668,8 @@ private static void deleteView(RestClient client, String viewName, Logger logger
         } catch (ResponseException e) {
             logger.info("View delete error: {}", e.getMessage());
             int code = e.getResponse().getStatusLine().getStatusCode();
-            // On older servers the view listing succeeds when it should, so we get here when we should not, hence the 400
-            if (code != 404 && code != 400) {
+            // On older servers the view listing succeeds when it should not, so we get here when we should not, hence the 400 and 500
+            if (code != 404 && code != 400 && code != 500) {
                 throw e;
             }
         }