convert: esx_addoninventory > bpt_addoninventory

[bitpredator]

Fixes #[issue_no]

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• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

New Feature Submissions:

1. Does your submission pass tests?
2. Have you lint your code locally prior to submission?

Changes to Core Features:

• converted code
• Adapt empiretown code to support bpt_addoninventory

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• Have you written new tests for your core changes, as applicable?
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