Add Youth Justice Board VPCs

[dms1981]

A reference to the issue / Description of it

#8706

How does this PR fix the problem?

Creates new Youth Justice Board business unit VPCs in line with our existing guidance.

How has this been tested?

Tested through CI pipeline checks

Deployment Plan / Instructions

Deploy through CI

Checklist (check x in [ ] of list items)

• I have performed a self-review of my own code
• All checks have passed
• I have made corresponding changes to the documentation
• Plan and discussed how it should be deployed to PROD (If needed)

Additional comments (if any)

{Please write here}

[github-actions]

Please check the plan carefully before deploying these changes.

⚠️ Making changes to the environments-networks/*.json files will affect the networking of MP AWS accounts, in particular which VPC/Subnet is being shared in to which environment. For more guidance consult the documentation.

[github-actions]

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Setting default tflint config...
Running tflint --init...
Installing "terraform" plugin...
Installed "terraform" (source: github.com/terraform-linters/tflint-ruleset-terraform, version: 0.9.1)
tflint will check the following folders:

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[markgov]

LGTM