[swsssdk-py] submodule update for sonic-py-swsssdk (#3929)

update multiDB changes in sonic-py-swsssdk, including:

- read portchannel name from LAG_NAME_MAP_TABLE in COUNTERS_DB (#51)
- Revert "read portchannel name from LAG_NAME_MAP_TABLE in COUNTERS_DB (#51)" (#57)
- [MultiDB] sonic-db-cli should support EVAL operation, app script use … (#58)

PR #3928 needs this swsssdk-py changes to work

Signed-off-by: Dong Zhang d.zhang@alibaba-inc.com