Inventory source misc bug fixes

Test inclusion requirements

In case the PR contains an enhancement or a new platform/service support, some tests have to be added for the new functionality:

any fix or enhancement SHOULD include relevant new tests or test updates, if any tests need updating.
a new platform support MUST include the relevant input files similar to what we have in tests/integration/sqcmds/-input directories, along with the relevant tests in the tests/integration/sqcmds/-samples dir. That list MUST include the all.yml file fully filled out.
any new service (or table) addition MUST include comments about what network OS are supported (along with version) with this command along with test samples for those platforms and input files in the *-input dir

For additional information about tests, follow this link

Fixes #

This PR contains the following fixes:

The type of device.port was 'str' instead of 'int'. This caused the poller to crash if device.port was used.
The content of device.port was always overridden by native source. Also when no port was specified

Please delete options that are not relevant.

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