Remove safe-contracts npm references

[dasanra]

Context / issue

Currently we are referencing safe-contracts npm package to get the smart contracts code to create types. The problem is that the protocol-kit needs to support several versions of the smart contracts at the same time, and fetching this npm packages produce dependencies inconsistencies that affect dependency management of the protocol-kit.

As these contracts are suposed not to be changed once compatible with the protocol kit, and also that they are only needed to generate types and execute tests, it's better that we reference or copy the necessary files directly.

Proposed solution

Copy the contract code to the protocol-kit repository of those versions that are final and stablished.

Alternatives

Sync with the protocol team if it could be possible to add types to safe-deployments or other helpers to enable the types and testing case on external projects.

[mmv08]

Sync with the protocol team if it could be possible to add types to safe-deployments or other helpers to enable the types and testing case on external projects.

Release 1.5.0 will include types for ethers v6