tezos.operations: missing None argument in handlers with optionals

[droserasprout]

🙏 Please, don't spam with "assign me" comments. If you understand what this ticket is about and want to help - just send a PR!

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Steps to reproduce:

Add index with optional: true item, init. Handler stub is union without default.

What did you expect to happen:

None arg passed

What actually happened:

It doesn't. Workaround: modify handler signature.

Environment

• Python version:
• DipDup version or commit hash: 8.5.0
• Database engine version:
• Hasura version:
• Are you in docker?
• Can you reproduce this issue on next?