StripeLocalCharge::getSource() returns wrong value

[Aerendir]

Used Versions

	Version
Stripe Bundle
Symfony
PHP

If you know other versions are affected, please indicate them below:

Description of the bug

TypeError: Return value of SerendipityHQ\Bundle\StripeBundle\Model\StripeLocalCharge::getSource() must be an instance of SerendipityHQ\Bundle\StripeBundle\Model\StripeLocalCard, string returned

Steps to reproduce

Steps to reproduce the behavior:
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Additional context

This error is returned by the tests.

I don't know which the correct behaviour should be. Investigate.