Pyband & Bandchain.js: Added get request evm proof on pyband and bandchain.js

[pzshine]

Fixed: #2961

Implementation details

• Pyband
  • Added new get_request_evm_proof_by_request_id including test and new EVMProof dataclass
  • Raised Error when the account doesn't exist on with_auto
• Bandchain.js
  • Added new getRequestEVMProofByRequestID including test and new EVMProof inteface

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