unable to query pxc_maint_mode while switching to maintenance

• Start a single node cluster.
• Switch pxc_maint_mode to maintenance.
• While prompt waits for pxc_maint_transition_period, query pxc_maint_mode from other client.
• Other client wait till the maint_transition_period.

Expected:

• Other client should return immediately so that proxysql can be update the status while and switch over the traffic.