Bump shell version

Change-Id: I4ebb9bc76bfea3d294f0fdb5a6b7aeb7a91a2d12

Author: ltangvald

VERSION

@@ -4,9 +4,9 @@ MYSQL_CLUSTER_VERSIONS["7.5"]=7.5.16
 MYSQL_CLUSTER_VERSIONS["7.6"]=7.6.12
 MYSQL_CLUSTER_VERSIONS["8.0"]=8.0.18
 declare -A MYSQL_SHELL_VERSIONS
-MYSQL_SHELL_VERSIONS["7.5"]=8.0.17
-MYSQL_SHELL_VERSIONS["7.6"]=8.0.17
-MYSQL_SHELL_VERSIONS["8.0"]=8.0.17
+MYSQL_SHELL_VERSIONS["7.5"]=8.0.18
+MYSQL_SHELL_VERSIONS["7.6"]=8.0.18
+MYSQL_SHELL_VERSIONS["8.0"]=8.0.18
 
 declare -A SERVER_VERSION_FULL
 SERVER_VERSION_FULL["7.5"]="${MYSQL_CLUSTER_VERSIONS["7.5"]}-${IMAGE_VERSION}"