Document AssemblyLoadContext changes for C++/CLI

[baronfel]

dotnet/runtime#56391 describes an issue that customers using C++/CLI may encounter when migrating from .NET Framework to .NET 5. This has come up in a few issues and would be good to have tracked in this document, since this is trying to be a one-stop shop for breaking changes.

The rationale for the change is captured in this comment and can be used for motivation.

Additional discussion on this topic can be found here, and this comment links to a community-authored sample of the suggested resolution.

For a permanent solution, this API proposal would be worth following.

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Document Details

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• ID: e8b64784-415c-7d00-3c44-aa3de496a54f
• Version Independent ID: 3d9c2faa-a7d7-ee5f-6f3c-87da5782a5cb
• Content: Breaking changes - .NET Framework to .NET Core
• Content Source: docs/core/compatibility/fx-core.md
• Product: dotnet-fundamentals
• GitHub Login: @gewarren
• Microsoft Alias: gewarren

[gewarren]

@baronfel Would this be a better place to note the issue? https://docs.microsoft.com/en-us/dotnet/core/porting/cpp-cli#known-issues

Also, it sounds like this problem will go away with .NET 7 based on dotnet/runtime#61105 (comment).

[baronfel]

Oh, that's great! So we'd need to note this for .net6.0 known-issues, but not .net7? I'm perfectly happy with that.