Subs table compatibility for PBC

[dparker1005]

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Changes proposed in this Pull Request:

Keeps subs table data in sync with Pay By Check Add On. Requires this PR to be merged into PBC in order to work correctly:
strangerstudios/pmpro-pay-by-check#110

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Changelog entry

Enter a summary of all changes on this Pull Request. This will appear in the changelog if accepted.

[kimcoleman]

Works in my testing and fixed issue I was seeing where the cancel on next payment date wasn't working for check gateway - approved ✔️