Reduce gcache size to cut down disk usage

mysql-test/suite/galera/galera_2nodes.cnf

@@ -16,7 +16,7 @@ wsrep-sync-wait=7
 #galera_port=@OPT.port
 #ist_port=@OPT.port
 #sst_port=@OPT.port
-wsrep_provider_options='base_port=@mysqld.1.#galera_port'
+wsrep_provider_options='base_port=@mysqld.1.#galera_port;gcache.size=10M'
 wsrep_sst_receive_address='127.0.0.1:@mysqld.1.#sst_port'
 
 [mysqld.2]
@@ -24,7 +24,7 @@ wsrep_sst_receive_address='127.0.0.1:@mysqld.1.#sst_port'
 #ist_port=@OPT.port
 #sst_port=@OPT.port
 wsrep_cluster_address='gcomm://127.0.0.1:@mysqld.1.#galera_port'
-wsrep_provider_options='base_port=@mysqld.2.#galera_port'
+wsrep_provider_options='base_port=@mysqld.2.#galera_port;gcache.size=10M'
 wsrep_sst_receive_address='127.0.0.1:@mysqld.2.#sst_port'
 
 [ENV]

mysql-test/suite/wsrep/my.cnf

@@ -5,5 +5,5 @@
 #galera_port=@OPT.port
 #ist_port=@OPT.port
 #sst_port=@OPT.port
-wsrep_provider_options='base_port=@mysqld.1.#galera_port'
+wsrep_provider_options='base_port=@mysqld.1.#galera_port;gcache.size=10M'