Update CLI template tutorials for .NET 5

[tdykstra]

Applies to this tutorial and the following 2:

• https://docs.microsoft.com/en-us/dotnet/core/tutorials/cli-templates-create-project-template
• https://docs.microsoft.com/en-us/dotnet/core/tutorials/cli-templates-create-template-pack

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Document Details

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• ID: d9cb6bd4-1194-91fa-014c-2e72d809e772
• Version Independent ID: c3fddda9-24c1-f20c-a1b6-6aeea61d6e53
• Content: Create an item template for dotnet new - .NET Core CLI - .NET Core
• Content Source: docs/core/tutorials/cli-templates-create-item-template.md
• Product: dotnet-fundamentals
• GitHub Login: @adegeo
• Microsoft Alias: adegeo