[BuildTool] New version for BepInEx needed

[Daniel Noeth]

Couldn't use the BepInEx 5.4.5 for current game version. Had to use this version:

private const string BepInExDownloadUrl =
    "https://github.com/BepInEx/BepInEx/releases/download/v5.4.19/BepInEx_x64_5.4.19.0.zip";

And I also updated UnityDoorstop: (was not necessary)

private const string UnityDoorstopDownloadUrl =
    "https://github.com/NeighTools/UnityDoorstop/releases/download/v3.4.0.0/Doorstop_x64_3.4.0.0.zip";
```