after-merge disable unstable tests

they used to be unstable, fixed in 7.1.8
and apparently broken again now

storage/tokudb/mysql-test/tokudb/t/i_s_tokudb_lock_waits_released.test

+if (`select @@tokudb_version < "5.6.27"`)
+{
+  --skip Race condition in the test in TokuDB below 5.6.27
+}
+
 # verify that information_schema.tokudb_locks gets populated with locks, information_schema.tokudb_lock_waits gets
 # populated with 1 lock_wait and all transactions are present in information_schema.tokudb_trx for 2 clients
 

storage/tokudb/mysql-test/tokudb/t/i_s_tokudb_locks_released.test

+if (`select @@tokudb_version < "5.6.27"`)
+{
+  --skip Race condition in the test in TokuDB below 5.6.27
+}
+
 # verify that information_schema.tokudb_locks gets populated with locks for 2 clients
 
 source include/have_tokudb.inc;