Delete build-test-prerequisites.ps1

With the build scripts moved to c# this is no longer required.

scripts/test/setup/build-test-prerequisites.ps1

@@ -1,45 +0,0 @@
-#
-# Copyright (c) .NET Foundation and contributors. All rights reserved.
-# Licensed under the MIT license. See LICENSE file in the project root for full license information.
-#
-
-. "$PSScriptRoot\..\..\common\_common.ps1"
-
-function buildTestPackages
-{
-    mkdir -Force $TestPackageDir
-
-    loadTestPackageList | foreach {
-        dotnet pack "$RepoRoot\TestAssets\TestPackages\$($_.ProjectName)" --output "$TestPackageDir"
-    
-        if (!$?) {
-            error "Command failed: dotnet pack"
-            Exit 1
-        }
-    }
-}
-
-
-function buildTestProjects
-{
-    $testProjectsRoot = "$RepoRoot\TestAssets\TestProjects"
-    $exclusionList = @("$testProjectsRoot\CompileFail\project.json")
-    $testProjectsList = (Get-ChildItem "$testProjectsRoot" -rec -filter "project.json").FullName
-
-    $testProjectsList | foreach {
-        if ($exclusionList -notcontains $_) {
-
-            Write-Host "$_"
-            dotnet build "$_"
-
-            if (!$?) {
-                error "Command failed: dotnet build"
-                Exit 1
-            }
-        }
-    }
-}
-
-buildTestPackages
-
-buildTestProjects