fix: loading multiple pxs at start time issues

[fcolarich]

What does this PR change?

SO, we were reusing the ServerAbout and it caused (when loading multiple PXs without delay) to sometimes load the wrong scenes for one of the PXs...
This is fixed now.
...

How to test the changes?

Open the client, it should load the PXs correctly and track the progress of the MF quests correctly as well.

[github-actions]

Windows and Mac build successfull in Unity Cloud! You can find a link to the downloadable artifact below.

Name	Link
Commit	76ebd1c
Logs	https://github.com/decentraland/unity-explorer/actions/runs/11942245906
Download Windows	https://github.com/decentraland/unity-explorer/suites/31139544414/artifacts/2215856888
Download Windows S3	https://explorer-artifacts.decentraland.org/@dcl/unity-explorer/branch/fix/loading_multiple_pxs_nono/Decentraland_windows64.zip
Download Mac	https://github.com/decentraland/unity-explorer/suites/31139544414/artifacts/2216112486
Download Mac S3	https://explorer-artifacts.decentraland.org/@dcl/unity-explorer/branch/fix/loading_multiple_pxs_nono/Decentraland_macos.zip
Built on	2024-11-20T23:56:43Z

[DafGreco]

Hey team ! Fix verified on both platforms ! UI appears properly on windows and macos ✅

This PR only fixes the missing UI from a user perspective but does not fix the progress tracking issue that we are currently having.