Fix release packaging build (#6459)
Fix release packaging build (#6459)

The release packaging build needs to have 'dotnet' in path, fixed that by adding Find-DotNet
Refactored restore logic so it can be used from both Start-PSBuild and Copy-PSGalleryModules

JamesWTruher/PowerShell-1,PaulHigin/PowerShell,daxian-dbw/PowerShell,daxian-dbw/PowerShell,JamesWTruher/PowerShell-1,PaulHigin/PowerShell,PaulHigin/PowerShell,JamesWTruher/PowerShell-1,JamesWTruher/PowerShell-1,daxian-dbw/PowerShell,TravisEz13/PowerShell,TravisEz13/PowerShell,TravisEz13/PowerShell,TravisEz13/PowerShell,PaulHigin/PowerShell,daxian-dbw/PowerShell