Multisig operations. Can't reject operation if has a proxy

[stepanLav]

Description

User can't reject the operation, confirmation page is empty, if user has proxy for signatory account.

Example

https://github.com/novasamatech/nova-spektr/assets/40560660/9942438f-5754-4582-a377-0849bd5be39a

Steps to Reproduce

1. Add 2 wallets in spektr, signatory_a and signatory_b
2. Create multisig wallet with 2 signatory, signatory_a and signatory_b
3. Create multisig transaction from signatory_a
4. Create proxy from signatory_ on signatory_b
5. Try to reject multisig operation

Expected Behavior

Should be taken original signatory_a account, successfull reject

Actual Behavior

May be taken a proxy account on confirmation screen, that lead to empty confirmation screen

Environment

• Operating system: macos
• Version: 1.7.3

[stepanLav]

We should remove proxied wallets from the list of signatories in multisig operations

[stepanLav]

Status verification: ✅