Updated the workshop to .NET 8 and Hot Chocolate 14

[glen-84]

⚠️ WIP

• [x] README.md
• [x] Creating a new GraphQL server project.
• [x] [Remove] Controlling nullability.
• [x] Understanding GraphQL query execution and DataLoader.
• [x] GraphQL schema design approaches.
• [x] Understanding middleware.
• [x] Adding complex filter capabilities.
• [x] Adding real-time functionality with subscriptions.
• [x] Testing the GraphQL server.
• [ ] (Dev-ops)

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To-do

• Append stable/keyset order when using [UseSorting].
• [Michael] Dev-ops.

[CLAassistant]

All committers have signed the CLA.

[michaelstaib]

Looks good so far