Fixes issue where selecting the "-------------" option in countries doesn't select the default country

[GordonArber]

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Proposed Changes

Fixes issue where selecting the "-------------" option in countries doesn't select the default country. Setting it to empty so it can properly use the default country.

Fixes: #6299

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[nairdo]

Hi @GordonArber I realize you submitted a partial fix for issue 6299 last week which was also just recently fixed by someone on the core team. I just wanted to say, although we weren't able to take this Pull Request, don't be discouraged. Having a community like you're part of is a tremendous asset to RockRMS! Thanks for helping make Rock "Better Together".