PS-9453: percona_telemetry causes a long wait on COND_thd_list due to…

… the absence of the root user

https://perconadev.atlassian.net/browse/PS-9453

Post push fix.

During the installation of Percona Telemetry Component we grant
'mysql.session' user with additional privileges.
It happens during the server startup, so servers started during the test
will have related timestamps different in general.
Some tests (e.g. clone plugin related) restore the clone instance state
by cloning the donor. In such a case restored instance will have
different timestamps at the beginning and the end of the test and MTR
check will complain because of different tables checksums.

Workaround this problem by excluding mysql.tables_priv from checksum
calculation. Instead, dump all tables privileges but without TIMESTAMP
column.

This is the same approach as for INFORMATION_SCHEMA.ROUTINES.

mysql-test/include/mtr_check.sql

@@ -210,6 +210,17 @@ BEGIN
       AND USER NOT IN ('unauthenticated user','mysql.session', 'event_scheduler')
         ORDER BY COMMAND;
 
+  -- During the installation of Percona Telemetry Component we grant 'mysql.session' user with additional privileges.
+  -- It happens during the server startup, so servers started during the test will have related timestamps different in general.
+  -- Some tests (e.g. clone plugin related) restore the clone instance state by cloning the donor. In such a case restored
+  -- instance will have different timestamps at the beginning and the end of the test and MTR check will complain because of
+  -- different tables checksums.
+  -- Workaround this problem by excluding mysql.tables_priv from checksum calculation. 
+  -- Instead, dump all tables privileges but without TIMESTAMP column.
+  -- This is the same approach as for INFORMATION_SCHEMA.ROUTINES above.
+  SELECT /*+SET_VAR(use_secondary_engine=OFF)*/ host, db, user, table_name, grantor, table_priv, column_priv
+    FROM mysql.tables_priv ORDER BY host, db, user, table_name;
+
   -- Checksum system tables to make sure they have been properly
   -- restored after test.
   -- skip mysql.proc however, as created timestamps may have been updated by
@@ -238,7 +249,6 @@ BEGIN
     mysql.replication_group_member_actions,
     mysql.role_edges,
     mysql.slow_log,
-    mysql.tables_priv,
     mysql.time_zone,
     mysql.time_zone_leap_second,
     mysql.time_zone_name,