Fix mariadb recover seqnum regex

Regex used to find the recover seqnum partition is not
returning the real num id rather a None.
Task fails due seqnum[0] is not iterable.

Change-Id: I1be55b6ebfc17c6d423e638662ec2a9f4b9b49a2
Closes-Bug: #1752128

ansible/roles/mariadb/tasks/recover_cluster.yml

@@ -43,7 +43,7 @@
       shell: "docker cp {{ mariadb_service.container_name }}:/var/log/kolla/mariadb/mariadb.log /tmp/mariadb_tmp.log"
 
     - name: Get MariaDB wsrep recovery seqno
-      shell: "tail -n 200 /tmp/mariadb_tmp.log | grep  Recovered | tail -1 | awk '{print $7}' | awk -F'\n' '{print $1}' | awk -F':' '{print $2}'"
+      shell: tail -n 200 /tmp/mariadb_tmp.log | awk -F" " '$0~/Recovered position/{print $NF;exit;}' | awk -F":" '{print $1}'
       register: wsrep_recovery_seqno
 
     - name: Removing MariaDB log file from /tmp