Remove DOTNET_STARTUP_HOOKS env workaround after dotnet/sdk#54922

[rolfbjarne]

In PR #25738 we added a temporary workaround in for sandboxed Mac Catalyst apps when sets to a path outside the app sandbox.\n\nCurrent workaround (lines ~86-90):\n- when , set \n- pass in \n\nThis should be removed/simplified once dotnet/sdk#54922 is merged and available in the SDK used by this repo.\n\nContext:\n- PR: #25738\n- SDK PR: https://github.com/dotnet/sdk/pull/54922\n