Give up, use CMD's rd

The prune command fails due to the error mentioned in the previous commit message.

Using PowerShell's Remove-Item is slow due to needing to create a .NET representation for each file before processing it.

Using [System.IO.Directory]::Delete throws an exception and gives up if any file can't be deleted.
Even though docker seems to be thoroughly killed, we don't have access to delete some of its files most of the time, which might be related to the original error that blocks the prune command.

CMD's rd should be as fast as anything else (except for the smallish overhead from creating a subprocess), and at least for Aussiemon, it seems to work.

.gitlab-ci.yml

@@ -717,7 +717,7 @@ macOS15_Xcode16_arm64:
   - Get-Volume
   # - docker system prune --all --volumes --force
   - Stop-Service docker
-  - '[System.IO.Directory]::Delete("C:\ProgramData\Application Data\docker", $true)'
+  - cmd /c rd /s /q "C:\ProgramData\Application Data\docker"
   - Get-Volume
   - Import-Module "$env:ChocolateyInstall\helpers\chocolateyProfile.psm1"
   - choco source add -n=openmw-proxy -s="https://repo.openmw.org/repository/Chocolatey/" --priority=1
@@ -954,7 +954,7 @@ Windows_Ninja_CacheInit:
   - Get-Volume
   # - docker system prune --all --volumes --force
   - Stop-Service docker
-  - '[System.IO.Directory]::Delete("C:\ProgramData\Application Data\docker", $true)'
+  - cmd /c rd /s /q "C:\ProgramData\Application Data\docker"
   - Get-Volume
   - Import-Module "$env:ChocolateyInstall\helpers\chocolateyProfile.psm1"
   - choco source add -n=openmw-proxy -s="https://repo.openmw.org/repository/Chocolatey/" --priority=1