fix msteams installer

Following:

https://answers.microsoft.com/en-us/msteams/forum/all/unable-to-install-the-new-teams-msix-silently/9e64bf40-3436-4c1f-8215-b58a926f444e

seems to work better than the previous command, which I'm sure I'd have tested but didn't lead to Teams being available on pyrrole.

packages/msteams.xml

@@ -10,7 +10,7 @@
 
     <check type='registry' condition='equals' path='%regkey%\version' value="%version%"/>
 
-    <install cmd='powershell Add-AppPackage %WPKGSOFTWARE%\microsoft.com\teams\%version%\msteams-x64.msix'/>
+    <install cmd='powershell Add-AppProvisionedPackage -online -packagepath %WPKGSOFTWARE%\microsoft.com\teams\%version%\msteams-x64.msix -skiplicense'/>
     <install cmd='reg add %regkey% /t reg_sz /v version /d %version% /f'/>
 
     <upgrade include='remove' />