force MSI package to install all files

Signed-off-by: Matthieu Gallien <matthieu.gallien@nextcloud.com>

admin/win/msi/Nextcloud.wxs

@@ -45,6 +45,7 @@
         https://www.joyofsetup.com/2010/01/16/major-upgrades-now-easier-than-ever/
     -->
     <MajorUpgrade Schedule="afterInstallInitialize" AllowDowngrades="yes" />
+    <Property Id="REINSTALLMODE" Value="amus" />
 
     <Media Id="1" Cabinet="$(var.AppShortName).cab" EmbedCab="yes" />