Minor release

No breaking changes expected.

Changes

Updated WebView2 dependency to version 1.0.3296.44.
- PowerShell 5.1 now uses net462 assemblies (previously net45).
- PowerShell 7+ continues to use netcoreapp3.0 assemblies.
Added optional User-Agent parameter for Invoke-OAuth2Authorization (WebView2).
New public function Convert-UnixTime converts between unix timestamps and DateTime in both directions.
- Replaces the previous internal function Get-UnixTime.
Internal refactoring
- Build scripts simplified and improved documentation, making custom builds and contributions easier.
- ConvertFrom-JsonWebToken internal refactor with improved error handling.