Fix scopesToMonitor parsing in script

[sandernaus]

🛠️ Description

Fixes the logic to generate the scopes in the settings.json.

• The object created for $newScopes is differently structure, compared to $json.scopes, resulting in not just merging them using the +
• The validation for scopes is wrongly set, as now the length of the dictionary is checked (which is 1), and not the length of the string value for the actual scope key, causing all scopes to be discarded

Fixes #1880

📋 Checklist

🔬 How did you test this change?

• 🤏 Lint tests
• 🤞 PS -WhatIf / az validate
• 👍 Manually deployed + verified
• 💪 Unit tests
• 🙌 Integration tests

🙋‍♀️ Do any of the following that apply?

• 🚨 This is a breaking change.
• 🤏 The change is less than 20 lines of code.

📑 Did you update docs/changelog.md?

• ✅ Updated changelog (required for dev PRs)
• ➡️ Will add log in a future PR (feature branch PRs only)
• ❎ Log not needed (small/internal change)

📖 Did you update documentation?

• ✅ Public docs in docs (required for dev)
• ✅ Internal dev docs in src (required for dev)
• ➡️ Will add docs in a future PR (feature branch PRs only)
• ❎ Docs not needed (small/internal change)

[sandernaus]

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