feat!: DBTP-1503 - Cross account deploy and manual release pipeline

[JohnStainsby]

Addresses https://uktrade.atlassian.net/browse/DBTP-1503

Follows on from #276

#282 has been merged into this PR due to major changes in the pipeline deploy stages. So this PR now addresses:

• Cross account permissions
• Manual release pipeline that can deploy any image to any environment, this can be triggered manually in the AWS console or CLI via platform-helper codebase deploy after the updates in this PR

Breaking change update:

1. This adds a role in the extensions module for each environment which the codebase pipeline assumes
2. The extensions module requires another args variable named pipeline_account_id
3. This will need to be added to the environment main.tf by running platform-helper environment generate-terraform --name <env>
4. Environments will need to be re-deployed before the codebase-pipelines

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Checklist:

Title:

• Scope included as per conventional commits
• Ticket reference included (unless it's a quick out of ticket thing)

Description:

• Link to ticket included (unless it's a quick out of ticket thing)
• Includes tests (or an explanation for why it doesn't)
• Includes any applicable changes to the documentation in this code base
• Includes link(s) to any applicable changes to the documentation in the DBT Platform Documentation (can be to a pull request)

Tasks:

• Trigger the pull request regression tests for this branch and confirm that they are passing