Update metadata for what's new topics

[gewarren]

• Removes redundant ms.topic type (already set in docfx.json)
• Set freshness expiry to 10 years

Related to #48472.

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docs/core/whats-new/dotnet-10/libraries.md	What's new in .NET libraries for .NET 10
docs/core/whats-new/dotnet-10/overview.md	What's new in .NET 10
docs/core/whats-new/dotnet-10/runtime.md	What's new in .NET 10 runtime
docs/core/whats-new/dotnet-10/sdk.md	What's new in the SDK and tooling for .NET 10
docs/core/whats-new/dotnet-5.md	docs/core/whats-new/dotnet-5
docs/core/whats-new/dotnet-6.md	What's new in .NET 6
docs/core/whats-new/dotnet-7.md	What's new in .NET 7
docs/core/whats-new/dotnet-8/containers.md	What's new in containers for .NET 8
docs/core/whats-new/dotnet-8/overview.md	docs/core/whats-new/dotnet-8/overview
docs/core/whats-new/dotnet-8/runtime.md	What's new in the .NET 8 runtime
docs/core/whats-new/dotnet-8/sdk.md	What's new in the SDK and tooling for .NET 8
docs/core/whats-new/dotnet-9/libraries.md	What's new in .NET libraries for .NET 9
docs/core/whats-new/dotnet-9/overview.md	What's new in .NET 9
docs/core/whats-new/dotnet-9/runtime.md	docs/core/whats-new/dotnet-9/runtime
docs/core/whats-new/dotnet-9/sdk.md	What's new in the SDK and tooling for .NET 9
docs/core/whats-new/dotnet-core-2-0.md	What's new in .NET Core 2.0
docs/core/whats-new/dotnet-core-2-1.md	What's new in .NET Core 2.1
docs/core/whats-new/dotnet-core-2-2.md	docs/core/whats-new/dotnet-core-2-2
docs/core/whats-new/dotnet-core-3-0.md	What's new in .NET Core 3.0
docs/core/whats-new/dotnet-core-3-1.md	What's new in .NET Core 3.1