[MM-19963] set working directory on start (#1105)

* [MM-19963] set current working directory for the app

* prevent failing if env variables are not setup

* [MM-19963] cwd if not in dev mode and only if necessary, log it if it happens

* fix remove path if no cert is present

* address CR suggestions

scripts/Makefile.ps1

@@ -439,7 +439,7 @@ function Get-Cert {
 }
 
 function Remove-Cert {
-    if (Test-Path $env:PFX) {
+    if (Test-Path 'env:PFX') {
         Print-Info "Removing windows certificate"
         Remove-Item -path "./mattermost-desktop-windows.pfx"
     }