Move temp folder into repo to avoid state that causes build errors from time to time when rebuilding locally (and packages have updated) (#903)

* Move temp folder into repo to avoid state that cannot be cleaned by cleaning the repo

* Add new .tmp directory to .gitignore

* Delete .tmp folder in Clean task

Author: bergmeister

.gitignore

@@ -5,6 +5,7 @@ obj
 objd
 out/
 tmp/
+.tmp
 App_Data
 *.user
 *.sln.cache

PowerShellEditorServices.build.ps1

@@ -129,7 +129,10 @@ function Restore-NugetAsmForRuntime {
         [string]$TargetRuntime = $script:WindowsPowerShellFrameworkTarget
     )
 
-    $tmpDir = [System.IO.Path]::GetTempPath()
+    $tmpDir = Join-Path $PSScriptRoot '.tmp'
+    if (-not (Test-Path $tmpDir)) {
+        New-Item -ItemType Directory -Path $tmpDir
+    }
 
     if (-not $DllName) {
         $DllName = "$PackageName.dll"
@@ -250,6 +253,7 @@ task SetupDotNet -Before Clean, Build, TestHost, TestServer, TestProtocol, Packa
 task Clean {
     exec { & $script:dotnetExe restore }
     exec { & $script:dotnetExe clean }
+    Remove-Item $PSScriptRoot\.tmp -Recurse -Force -ErrorAction Ignore
     Remove-Item $PSScriptRoot\module\PowerShellEditorServices\bin -Recurse -Force -ErrorAction Ignore
     Remove-Item $PSScriptRoot\module\PowerShellEditorServices.VSCode\bin -Recurse -Force -ErrorAction Ignore
     Get-ChildItem -Recurse $PSScriptRoot\src\*.nupkg | Remove-Item -Force -ErrorAction Ignore