Fixing dotnet SDK version parsing in build.psm1 (PowerShell#17198)

Author: powercode

build.psm1

@@ -2196,7 +2196,19 @@ function Start-PSBootstrap {
 
 function Get-LatestInstalledSDK {
     Start-NativeExecution -sb {
-        dotnet --list-sdks | Select-String -Pattern '\d*.\d*.\d*(-\w*\.\d*.\d*.\d*)?' | ForEach-Object { [System.Management.Automation.SemanticVersion]::new($_.matches.value) } | Sort-Object -Descending | Select-Object -First 1
+        dotnet --list-sdks | ForEach-Object {
+            # this splits strings like
+            # '6.0.202 [C:\Program Files\dotnet\sdk]'
+            # '7.0.100-preview.2.22153.17 [C:\Users\johndoe\AppData\Local\Microsoft\dotnet\sdk]'
+            # into version and path parts.
+            $version, $null = $_ -split '\s',2
+            try {
+                [System.Management.Automation.SemanticVersion]::new($version)
+            }
+            catch {
+                Write-Warning -Message "Unable to parse dotnet version semantically: $version"
+            }
+        } | Sort-Object -Descending | Select-Object -First 1
     } -IgnoreExitcode 2> $null
 }