release: bump to v0.40.0

[kayagokalp]

Description

Waiting for:

• Upgrade to fuel-core 0.18.1 and fuels-rs 0.41 #4525.

@Dhaiwat10 was waiting for a release with the linked PR merged.

@IGI-111 I had the PR ready, leaving it up to you when to merge & cut the release. Made this a major bump as we had a breaking change merged (#4574).

Checklist

• I have linked to any relevant issues.
• I have commented my code, particularly in hard-to-understand areas.
• I have updated the documentation where relevant (API docs, the reference, and the Sway book).
• I have added tests that prove my fix is effective or that my feature works.
• I have added (or requested a maintainer to add) the necessary Breaking* or New Feature labels where relevant.
• I have done my best to ensure that my PR adheres to the Fuel Labs Code Review Standards.
• I have requested a review from the relevant team or maintainers.

[Dhaiwat10]

Thanks @kayagokalp!