Blazor tutorial update for .NET 8

[guardrex]

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Document Details

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• ID: 23f2cad2-31f9-d5d1-671c-5613fb812b19
• Version Independent ID: 23f2cad2-31f9-d5d1-671c-5613fb812b19
• Content: Build a Blazor todo list app
• Content Source: aspnetcore/blazor/tutorials/build-a-blazor-app.md
• Product: aspnet-core
• Technology: aspnetcore-tutorials
• GitHub Login: @guardrex
• Microsoft Alias: riande