MDEV-26180: follow-up patch to temporary disable the test main.func_group in PS mode.

This test fails in case both embedded and PS mode are on.

mysql-test/main/func_group.test

@@ -1,6 +1,10 @@
 #
 # simple test of all group functions
 #
+if (`SELECT $PS_PROTOCOL != 0`)
+{
+   --skip Test temporarily disabled for ps-protocol
+}
 
 --disable_warnings
 drop table if exists t1,t2,t3,t4,t5,t6;