Add TEST_ACCOUNT_CLIENT_ID & TEST_ACCOUNT_CLIENT_SECRET

[marrobi]

As per #144 , these vars are need to register bundles in an unattended manner in the pipelines.

[Copilot]

Pull Request Overview

This PR adds two new environment variables TEST_ACCOUNT_CLIENT_ID and TEST_ACCOUNT_CLIENT_SECRET to GitHub Actions workflows to enable unattended bundle registration in CI/CD pipelines.

• Adds test account credentials as required secrets to workflows
• Implements validation for the new required secrets
• Passes the credentials through to the devcontainer execution environment

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
.github/workflows/register_tre_bundle.yml	Passes test account credentials as environment variables
.github/workflows/deploy_tre_reusable.yml	Defines test account secrets as required inputs and adds validation checks
.github/workflows/deploy_tre_branch.yml	Passes test account credentials to deployment workflow
.github/workflows/deploy_tre.yml	Passes test account credentials to deployment workflow
.github/actions/devcontainer_run_command/action.yml	Defines test account inputs and passes them to container environment

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