Fail Firewall migration if there's no firewall

[tanya-borisova]

Resolves #2791

What is being addressed

Explicitly fail Firewall migration if there is no firewall deployed.

[github-actions]

Unit Test Results

517 tests   517 ✔️  18s ⏱️
    1 suites      0 💤
    1 files        0 ❌

Results for commit 5e98138.

♻️ This comment has been updated with latest results.

[tanya-borisova]

/test-extended

[github-actions]

🤖 pr-bot 🤖

🏃 Running extended tests: https://github.com/microsoft/AzureTRE/actions/runs/3337580424 (with refid adc1d249)

(in response to this comment from @tanya-borisova)

[tanya-borisova]

/test-destroy-env

[github-actions]

Destroying branch test environment (RG: rg-tre0971c40c)... (run: https://github.com/microsoft/AzureTRE/actions/runs/3362380106)

[github-actions]

Destroying PR test environment (RG: rg-treadc1d249)... (run: https://github.com/microsoft/AzureTRE/actions/runs/3362380106)

[github-actions]

Branch test environment destroy complete (RG: rg-tre0971c40c)

[github-actions]

PR test environment destroy complete (RG: rg-treadc1d249)

[tanya-borisova]

/test

[github-actions]

🤖 pr-bot 🤖

🏃 Running tests: https://github.com/microsoft/AzureTRE/actions/runs/3362655514 (with refid adc1d249)

(in response to this comment from @tanya-borisova)