fix(lab): release T-014 process handles before cleanup [T-014]

Sense/scripts/t014-capacity.ps1

@@ -146,6 +146,29 @@ function Stop-AllManagedProcesses($Items) {
     if ($remaining.Count -gt 0) {
         Write-Warning "managed processes did not exit within the shared cleanup deadline: $($remaining.Count)"
     }
+    foreach ($item in $processes) {
+        if ($item.Process.HasExited) {
+            $item.Stdout.Wait(2000) | Out-Null
+            $item.Stderr.Wait(2000) | Out-Null
+            $item.Process.Dispose()
+        }
+    }
+}
+
+function Remove-SessionDirectory([string]$Path) {
+    Get-ChildItem -LiteralPath $Path -Recurse -Force -ErrorAction SilentlyContinue |
+        ForEach-Object { $_.Attributes = 'Normal' }
+    (Get-Item -LiteralPath $Path -Force).Attributes = 'Directory'
+    $deleteWatch = [Diagnostics.Stopwatch]::StartNew()
+    while (Test-Path -LiteralPath $Path) {
+        try {
+            Remove-Item -LiteralPath $Path -Recurse -Force -ErrorAction Stop
+        }
+        catch {
+            if ($deleteWatch.Elapsed.TotalSeconds -ge 10) { throw }
+            Start-Sleep -Milliseconds 200
+        }
+    }
 }
 
 function Assert-Alive($Managed) {
@@ -920,10 +943,7 @@ finally {
             throw 'refusing to clean an unexpected T-014 session path'
         }
         if (Test-Path -LiteralPath $resolvedSession) {
-            Get-ChildItem -LiteralPath $resolvedSession -Recurse -Force -ErrorAction SilentlyContinue |
-                ForEach-Object { $_.Attributes = 'Normal' }
-            (Get-Item -LiteralPath $resolvedSession -Force).Attributes = 'Directory'
-            Remove-Item -LiteralPath $resolvedSession -Recurse -Force
+            Remove-SessionDirectory $resolvedSession
         }
     }
     else {