fix(database): Fix public_key_credential_id length

[zevlee]

• Resolves: https://github.com/nextcloud/server/issues/34476

Summary

Increases length of column for security key so that it fits. This is essentially an identical migration step to https://github.com/nextcloud/twofactor_webauthn/pull/323.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• [ ] Tests (unit, integration, api and/or acceptance) are included
• [ ] Screenshots before/after for front-end changes
• [ ] Documentation (manuals or wiki) has been updated or is not required
• [ ] Backports requested where applicable (ex: critical bugfixes)