#### Why I did it
Update scripts in sonic-buildimage from py-swsssdk to swsscommon
#### How I did it
Change code to use swsscommon.
#### How to verify it
Pass all E2E test case
#### Which release branch to backport (provide reason below if selected)
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- [ ] 201811
- [ ] 201911
- [ ] 202006
- [ ] 202012
- [ ] 202106
- [ ] 202111
- [ ] 202205
#### Description for the changelog
Update scripts in sonic-buildimage from py-swsssdk to swsscommon
#### Link to config_db schema for YANG module changes
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#### A picture of a cute animal (not mandatory but encouraged)
This PR is in preparation to move from snmp.yml to configdb. This will more closely align with other commands in sonic and use configdb as the source of truth for snmp configuration.
Note: This is the first of 2 PR's to enable this. This PR will not change any functionality but will allow the snmp.yml file info to be put into the configdb.
Created a script that takes the snmp.yml variables and converts them to the configdb format.
Added file to dockerfile.j2 so that file is copied in the container.
Updated start.sh file to automatically run the python conversion script each time the docker container is restarted.
