MDEV-29892 : Galera test failure on galera_sr_kill_slave_after_apply_rollback2

Could not reproduce and bug report is incomplete i.e. there
is no error logs to analyze and 10.4 branch commit where
failure was seen is not mentioned. Enable test to get more information.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

mysql-test/suite/galera_3nodes_sr/disabled.def

@@ -9,5 +9,3 @@
 #  Do not use any TAB characters for whitespace.
 #
 ##############################################################################
-
-galera_sr_kill_slave_after_apply_rollback2 : MDEV-29892 Galera test failure on galera_sr_kill_slave_after_apply_rollback2