Improve the error message when the SetAuthenticatedUserContext called too early

[Pavel Zhur]

If I call the SetAuthenticatedUserContext before the host.RunAsync(), apparently the IJsRuntime is not available for the IApplicationInsights service yet, and I'm getting this error in the console:

Error: One or more errors occurred. (Value cannot be null. (Parameter 'jsRuntime'))
    at Jn (marshal-to-js.ts:349:18)
    at Ul (marshal-to-js.ts:306:28)
    at do_icall (03bff762:0x1e5b2)
    at do_icall_wrapper (03bff762:0x19519)
    at mono_interp_exec_method (03bff762:0xb447)
    at interp_entry (03bff762:0x1c94a)
    at interp_entry_static_0 (03bff762:0x1d40e)
    at wasm_native_to_interp_System_Private_CoreLib_ThreadPool_BackgroundJobHandler (03bff762:0x2a542d)
    at mono_background_exec (03bff762:0x4eb7c)
    at e.<computed> (cwraps.ts:338:24)

Looking at this error, it is hard to guess that the workaround is to call the InitJSRuntime explicitly.
It would be nice if the error message was more meaningful and included a suggestion.