[importer] disable check on country attribute in incident model

[tlongers]

Where a value in incident:location has no match in the locations dataset, the importer reports two errors:

• the location doesn't exist; and,
• the country code is missing.

Code:

https://github.com/security-force-monitor/sfm-cms/blob/c8a00b435ac57732d767617c28eef264aed9f9d4/sfm_pc/management/commands/import_country_data.py#L2168-L2173

The data sheet does not contain an incident:country attribute to check, so the report is misleading. Unless it does something else that I can't see, I suggest removing this check.

[hancush]

Makes sense.