Fix GC card naming

[bodgit]

• Use correct file extension.
• Include the publisher code in the filenames.

Fixes #2

[coveralls]

Pull Request Test Coverage Report for Build 3857754617

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.5%) to 69.492%

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Totals
Change from base Build 3857684923:	0.5%
Covered Lines:	123
Relevant Lines:	177

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 3857754617

• 12 of 12 (100.0%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.5%) to 69.492%

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Totals
Change from base Build 3857684923:	0.5%
Covered Lines:	123
Relevant Lines:	177

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💛 - Coveralls