Support Unicode 9.0.0 in Fleet

[getvictor]

Goal

User story
As a Fleet admin,
I want to use Unicode 9.0.0 (emojis, accents, etc.) in any Fleet string fields
so that I can express myself better.

Context

Now that we don't support MySQL 5.7, we can switch to using the default MySQL 8.0 collation: utf8mb4_0900_ai_ci, which supports Unicode 9.0.0 and is accent-insensitive. The data is still stored in the same format, but sorting and equality operations are updated.

This was discussed in Backend sync: https://us-65885.app.gong.io/call?id=8041045095900447703

• Requestor(s): _____
• Product designer: _____

Changes

Product

• [ ] Reference documentation changes: TODO
• [ ] UI changes: TODO
• [ ] CLI (fleetctl) usage changes: TODO
• [ ] YAML changes: TODO
• [ ] REST API changes: TODO
• [ ] Fleet's agent (fleetd) changes: TODO
• [ ] Permissions changes: TODO
• [ ] Changes to paid features or tiers: TODO

Engineering

• [ ] Feature guide changes: TODO
• [ ] Database schema migrations: TODO
• [ ] Load testing: TODO

ℹ️  Please read this issue carefully and understand it. Pay special attention to UI wireframes, especially "dev notes".

QA

Risk assessment

• Requires load testing: TODO
• Risk level: Low / High TODO
• Risk description: TODO

Manual testing steps

1. Step 1
2. Step 2
3. Step 3

Testing notes

Confirmation

1. [ ] Engineer (@____): Added comment to user story confirming successful completion of QA.
2. [ ] QA (@____): Added comment to user story confirming successful completion of QA.

[lukeheath]

Thanks for filing! Historically, changing the database collation has been a source of pain during migrations. It works well for us, but there's so much diversity of data across all instances of Fleet that we inevitably end up failing some migrations, which creates a fire drill.

For that reason, I'm inclined to not prioritize this unless this a strong value proposition to justify making a risky collation change.