Update version to v0.8.10

[ethedev]

Description

The onchain proposals are using an old solidity version, v0.5.15. Moving forward we need to upgrade it and use v0.8.10 instead.

Requirements

• Upgrading the upcoming proposals contracts to use v0.8.10
• Adding tests to make sure everything is working properly

@ethedev as the proposal contracts are already upgraded to v0.8.10 I think we can close this issue.