CI: Fix empty generator identifier for x64 builds using buildspec.json

.github/scripts/Build-Windows.ps1

@@ -26,7 +26,7 @@ if ( $PSVersionTable.PSVersion -lt '7.0.0' ) {
 
 function Build {
     trap {
-        Pop-Location -Stack BuildTemp
+        Pop-Location -Stack BuildTemp -ErrorAction 'SilentlyContinue'
         Write-Error $_
         exit 2
     }
@@ -54,7 +54,7 @@ function Build {
     Setup-Host
 
     if ( $CmakeGenerator -eq '' ) {
-        $CmakeGenerator = $VisualStudioVersion
+        $CmakeGenerator = $script:VisualStudioVersion
     }
 
     (Get-Content -Path ${ProjectRoot}/CMakeLists.txt -Raw) `

.github/scripts/utils.pwsh/Setup-Obs.ps1

@@ -52,7 +52,7 @@ function Setup-Obs {
         $DepsPath = "plugin-deps-${script:DepsVersion}-qt${script:QtVersion}-${script:Target}"
 
         $CmakeArgs = @(
-            '-G', $script:CmakeGenerator
+            '-G', $CmakeGenerator
             "-DCMAKE_SYSTEM_VERSION=${script:PlatformSDK}"
             "-DCMAKE_GENERATOR_PLATFORM=$(if (${script:Target} -eq "x86") { "Win32" } else { "x64" })"
             "-DCMAKE_BUILD_TYPE=${script:Configuration}"