unable to execute unit test for "config interface" commands

[stephenxs]

Description

Unable to execute the unit test for config interface sub commands.
For unit testing to work for a command, the fixture @clicommon.pass_db is required.
However, the db objects are generated in interface subcommand instead of passed by @clicommon.pass_db. This is probably because the namespace is required in the config interface command especially for MULTI ASIC feature.

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[anshuv-mfst]

@stephenxs - could you please recheck; PRs are available.