Fix PWPush Pro account dropdown not populating

The backend was checking for `PWPushPro` field which doesn't exist in the
frontend configuration. The frontend sets `UseBearerAuth` to indicate a
PWPush Pro hosted account with Bearer authentication.

Changed the condition from:
  $Configuration.PWPushPro -eq $true
to:
  $Configuration.UseBearerAuth -eq $true

This aligns with the frontend's Extensions.json which uses `PWPush.UseBearerAuth`
to indicate Pro/hosted accounts.

Fixes KelvinTegelaar/CIPP#5057

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: lacymooretx

Modules/CippExtensions/Public/PwPush/Get-PwPushAccount.ps1

@@ -1,7 +1,7 @@
 function Get-PwPushAccount {
     $Table = Get-CIPPTable -TableName Extensionsconfig
     $Configuration = ((Get-CIPPAzDataTableEntity @Table).config | ConvertFrom-Json).PWPush
-    if ($Configuration.Enabled -eq $true -and $Configuration.PWPushPro -eq $true) {
+    if ($Configuration.Enabled -eq $true -and $Configuration.UseBearerAuth -eq $true) {
         Set-PwPushConfig -Configuration $Configuration
         Get-PushAccount
     } else {