Change: Adds latestDeployment for Environment

[CGoodwin90]

General Checklist

• Affected Issues have been mentioned in the Closing issues section
• Documentation has been written/updated
• PR title is ready for inclusion in changelog

Adds minimal field resolver latestDeployment to Environment.

Required for uselagoon/lagoon-beta-ui#148

[github-actions]

Overview

Image reference	testlagoon/api:main	lagoon/api:ci-latest
- digest	97b436889d7c	d98d826760b5
- tag	main	ci-latest
- vulnerabilities
- platform	linux/amd64	linux/amd64
- size	151 MB	182 MB (+31 MB)
- packages	1579	1579
Base Image	node:22-alpine also known as: • 22-alpine3.23 • 22.22-alpine • 22.22-alpine3.23 • jod-alpine • jod-alpine3.23	node:22-alpine also known as: • 22-alpine3.23 • 22.22-alpine • 22.22-alpine3.23 • jod-alpine • jod-alpine3.23
- vulnerabilities