Workaround because the revocation registry fix cannot update accumulator stored in Indy SDK storage

[swcurran]

Recently, an endpoint was added to "fix" an out of sync RevReg. Out of sync in this case can be caused by an Issuer trying to revoke a credential, but the update on the ledger failing, leaving the two out of sync. To address this, an ACA-Py endpoint was added that recalculated the accumulator from the list of revoked credentials, and updates the ledger. However, this still does not prevent future revocation errors when using the Indy SDK storage (indy-wallet) because it retains a copy of the accumulator that cannot be updated using the (current) Indy SDK.

A possible workaround to this issue for the Indy SDK is to catch the exception that occurs when a credential is revoked and immediately invoke the "fix RevReg" endpoint. This results in the ledger being accurate (which is what is important), and the accumulator in the Indy SDK storage remaining out of sync.

A better fix is possible with Askar as it can update the accumulator and will be added as another issue to be addressed.