Update Windows Server 2019 VM images — end of mainstream support

An org-wide audit of the dotnet org found references to Windows Server 2019 VM images. Windows Server 2019 ended mainstream support in January 2024.

Part of [.NET OS Support Tracking](https://github.com/dotnet/core/issues/9638). See also: [dotnet/runtime#125690](https://github.com/dotnet/runtime/issues/125690), [dotnet/dotnet-buildtools-prereqs-docker#1605](https://github.com/dotnet/dotnet-buildtools-prereqs-docker/issues/1605).

## Tracking

- [x] `.vsts-dotnet-ci.yml` — `1es-windows-2019-open` → `1es-windows-2022-open`
- [x] `build/codecoverage-ci.yml` — `1es-windows-2019-open` → `1es-windows-2022-open`
- [ ] `build/.night-build.yml` — `vmImage: windows-2019` → `vmImage: windows-2022`
- [ ] `build/.outer-loop-build.yml` — `vmImage: windows-2019` → `vmImage: windows-2022`

## Details

https://github.com/dotnet/machinelearning/blob/f79b8fa46965cd945e61151a6a67b885a6325b5a/.vsts-dotnet-ci.yml

https://github.com/dotnet/machinelearning/blob/f79b8fa46965cd945e61151a6a67b885a6325b5a/build/codecoverage-ci.yml#L51

https://github.com/dotnet/machinelearning/blob/f79b8fa46965cd945e61151a6a67b885a6325b5a/build/.night-build.yml

https://github.com/dotnet/machinelearning/blob/f79b8fa46965cd945e61151a6a67b885a6325b5a/build/.outer-loop-build.yml

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This issue was generated by GitHub Copilot CLI v1.0.7 via the [`update-supported-os`](https://github.com/dotnet/core/blob/main/.github/skills/update-supported-os/SKILL.md) skill.