Backport the migration contract to v1.4.1

[nlordell]

Context / issue

We are in the process of auditing additional Safe library contracts that need to be used by the Wallet team. At the current time, the library contracts planned for audit are:

• The Safe v1.3.0 to v1.4.1 migration contract
• The Safe L1 to L2 migration contract
• The Safe cross-chain setup contract

These changes should be made to the v1.4.1 branch, as we will be deploying these as additional v1.4.1 library contracts.

Proposed solution

Ensure that all of the planned audited contracts are part of the deployment scripts.

Alternatives

Require manual deployments for these contracts

Expected Outcome

A dev/v1.4.1 branch with backports including:

• Library contracts that are to be deployed
• Deployment scripts introduced in 1.

[nlordell]

This is in the 1.4.1-2 branch.