nupkg files require all architectures even with selective builds

While https://github.com/cefsharp/cef-binary/pull/100 initially covered this the final implementation either intentionally or not no longer templates the spec files.

This can cause it to try and restore arm64 binaries when only x64 packages are built. This doesn't require major changes but for arm64 removal for example modifying:
https://github.com/cefsharp/cef-binary/blob/master/NuGet/chromiumembeddedframework.runtime.json?#L13-L17

and potentially:
https://github.com/cefsharp/cef-binary/blob/master/NuGet/chromiumembeddedframework.runtime.nuspec?#L30

it requires some in the main project too (as otherwise the manual copies still try) but probably there straight conditionals would work:
https://github.com/cefsharp/CefSharp/blob/05577b7bf3933a057d42dabe0dc915676f9463a8/NuGet/PackageReference/CefSharp.Common.NETCore.targets?#L204-L224

I can do another PR to either remove these lines when select architectures are specified or go back to a templating system or nothing if it isn't desired for general support of select building.

首先，将打包文件 NuGet/chromiumembeddedframework.runtime.json 和 NuGet/chromiumembeddedframework.runtime.nuspec 与链接的 CefSharp.Common.NETCore.targets 部分进行比较。跟踪选择性架构构建如何影响包还原和手动复制。完成的标准是，仅 x64 构建不再需要或尝试还原 arm64 二进制文件。

由索引模型根据 Issue 内容生成。