[AOE] Reservations Usage workbook uses the most recent reservation display name

[helderpinto]

🛠️ Description

The Reservations Usage workbook has a Reservation filter that is preloaded with the list of all the active reservations. This fix ensure the latest reservation display name is used (in case the reservation display name changed over the course of the lookback period.

Fixes #1455

📋 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)