build(win): use UCRT64 environment instead of MinGW64.

[tez011]

Description

https://github.com/LizardByte/Sunshine/pull/2149 was reverted in https://github.com/LizardByte/Sunshine/pull/2320 and needs to be split into three changes:

• C++20
• UCRT64 (this one!)
• WGC

If https://github.com/msys2/MINGW-packages/pull/20477 is integrated, WGC can proceed without this change.

Screenshot

Issues Fixed or Closed

Type of Change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected) 🤪
• [x] Dependency update (updates to dependencies)
• [ ] Documentation update (changes to documentation)
• [x] Repository update (changes to repository files, e.g. .github/...)

Checklist

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have added or updated the in code docstring/documentation-blocks for new or existing methods/components

Branch Updates

LizardByte requires that branches be up-to-date before merging. This means that after any PR is merged, this branch must be updated before it can be merged. You must also Allow edits from maintainers.

• [x] I want maintainers to keep my branch updated