[#3592] MySql and Posgresql CB updated

[#3592] MySql and Posgresql CB updated

modified:   src/hooks/dhcp/mysql/mysql_cb_dhcp4.cc
modified:   src/hooks/dhcp/mysql/mysql_cb_dhcp6.cc
modified:   src/hooks/dhcp/mysql/mysql_query_macros_dhcp.h
modified:   src/hooks/dhcp/pgsql/pgsql_cb_dhcp4.cc
modified:   src/hooks/dhcp/pgsql/pgsql_cb_dhcp6.cc
modified:   src/hooks/dhcp/pgsql/pgsql_query_macros_dhcp.h
modified:   src/lib/dhcpsrv/testutils/generic_cb_dhcp4_unittest.cc
modified:   src/lib/dhcpsrv/testutils/generic_cb_dhcp6_unittest.cc