Fix sync mailboxes script dicker image

migration/Sync-Mailboxes.ps1

@@ -1,7 +1,7 @@
 #requires -Version 5.1
 <#
 .SYNOPSIS
-  Runs imapsync (via the dockerized imapsync/imapsync image) for every account
+    Runs imapsync (via the upstream gilleslamiral/imapsync image) for every account
   in a migration accounts.csv, copying mail from docker-mailserver to Stalwart.
 #>
 param(
@@ -24,7 +24,7 @@ foreach ($row in $rows) {
     Write-Host "==> Syncing $($row.email)"
 
     $dockerArgs = @(
-        "run", "--rm", "imapsync/imapsync",
+        "run", "--rm", "gilleslamiral/imapsync", "imapsync",
         "--host1", $SourceHost, "--port1", $SourcePort, "--ssl1",
         "--user1", $row.email, "--password1", $row.old_password,
         "--host2", $DestHost, "--port2", $DestPort, "--ssl2",