Uninit Windows Runtime

[vbrandl]

The winrt doc for uninit states

Unitializes the Windows Runtime. This must not be called as long as any Windows Runtime object is still alive.

(https://docs.rs/winrt/*/x86_64-pc-windows-msvc/winrt/struct.RuntimeContext.html#method.uninit)

From my understanding, this might cause issues, if multiple threads try to send notifications. Once the first thread is finished, uninit is called, while other threads might still require the runtime. I cannot test if there are any actual implications.