Polkadot: Update Dependency on `contract-extrinsics`

[tareknaser]

At the time Aqd was initially written, it depended on contract-extrinsics at commit dfdc768, which was an alpha version 4 pre-release.

Since then, both cargo-contract and contract-extrinsics (now at version "4.0.2") have undergone significant changes. Many functionalities have been transitioned from contract-extrinsics to cargo-contract including:

• Signing
• Chain logic
• Parsing balance and code hashes

Relevant pull requests:

• Simplify extrinisics crate and remove printing logic use-ink/cargo-contract#1495
• Remove chain logic from extrinsics crate use-ink/cargo-contract#1568

We need to update our dependency on contract-extrinsics to use the newer version, but it will require some refactoring to aqd-polkadot