src/installation/elsa-studio/ElsaStudioBlazorServer sample does crash at login

When I download the sample and do want to run it, it doesn't work:

**First**, the `Elsa.Api.Client` nuget is missing from the sample. I can add this myself, no problem.

**Second**, no that the project builds and the login page appears, I can input `admin` and `password`. But then the blazor ui crashes with a `HttpRequestException`.

```
System.Net.Http.HttpRequestException: Es konnte keine Verbindung hergestellt werden, da der Zielcomputer die Verbindung verweigerte. (localhost:5001)
---> System.Net.Sockets.SocketException (10061): Es konnte keine Verbindung hergestellt werden, da der Zielcomputer die Verbindung verweigerte.
at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.ThrowException(SocketError error, CancellationToken cancellationToken)
at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.System.Threading.Tasks.Sources.IValueTaskSource.GetResult(Int16 token)
at System.Net.Sockets.Socket.g__WaitForConnectWithCancellation|281_0(AwaitableSocketAsyncEventArgs saea, ValueTask connectTask, CancellationToken cancellationToken)
at System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(String host, Int32 port, HttpRequestMessage initialRequest, Boolean async, CancellationToken cancellationToken)
--- End of inner exception stack trace ---
at System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(String host, Int32 port, HttpRequestMessage initialRequest, Boolean async, CancellationToken cancellationToken)
at System.Net.Http.HttpConnectionPool.ConnectAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
at System.Net.Http.HttpConnectionPool.CreateHttp11ConnectionAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
at System.Net.Http.HttpConnectionPool.AddHttp11ConnectionAsync(QueueItem queueItem)
at System.Threading.Tasks.TaskCompletionSourceWithCancellation`1.WaitWithCancellationAsync(CancellationToken cancellationToken)
at System.Net.Http.HttpConnectionPool.HttpConnectionWaiter`1.WaitForConnectionAsync(Boolean async, CancellationToken requestCancellationToken)
at System.Net.Http.HttpConnectionPool.SendWithVersionDetectionAndRetryAsync(HttpRequestMessage request, Boolean async, Boolean doRequestAuth, CancellationToken cancellationToken)
at System.Net.Http.DiagnosticsHandler.SendAsyncCore(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
at System.Net.Http.RedirectHandler.SendAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
at System.Net.Http.HttpClient.g__Core|83_0(HttpRequestMessage request, HttpCompletionOption completionOption, CancellationTokenSource cts, Boolean disposeCts, CancellationTokenSource pendingRequestsCts, CancellationToken originalCancellationToken)
at Refit.RequestBuilderImplementation.<>c__DisplayClass14_0`2.<b__0>d.MoveNext() in /_/Refit/RequestBuilderImplementation.cs:line 256
--- End of stack trace from previous location ---
at Elsa.Studio.Login.Services.DefaultCredentialsValidator.ValidateCredentialsAsync(String username, String password, CancellationToken cancellationToken)
at Elsa.Studio.Login.Pages.Login.Login.ValidateCredentials(String username, String password)
at Elsa.Studio.Login.Pages.Login.Login.TryLogin()
at Elsa.Studio.Components.StudioComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
at Elsa.Studio.Components.StudioComponentBase.InvokeWithBlazorServiceContext(Func`1 func)
at Microsoft.AspNetCore.Components.Forms.EditForm.HandleSubmitAsync()
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState)
Microsoft.AspNetCore.Components.Server.Circuits.CircuitHost: Error: Unhandled exception in circuit 'PdOc5BnTLF9Q39X-OOnbleQxTZiIJasl0hI1wIr6oGk'.
```

This is probably, because the `appsettings.json` points to `https://localhost:5001/elsa/api` as backend while the server runs on `"applicationUrl": "https://localhost:53214;http://localhost:53215"`.

I can also change this to point to the right endpoint

**Third**, now that appsettings point to the app url, if I try to login again, I get this error:

```
Refit.ApiException: Response status code does not indicate success: 400 (Bad Request).
at Refit.RequestBuilderImplementation.<>c__DisplayClass14_0`2.<b__0>d.MoveNext() in /_/Refit/RequestBuilderImplementation.cs:line 288
--- End of stack trace from previous location ---
at Elsa.Studio.Login.Services.DefaultCredentialsValidator.ValidateCredentialsAsync(String username, String password, CancellationToken cancellationToken)
at Elsa.Studio.Login.Pages.Login.Login.ValidateCredentials(String username, String password)
at Elsa.Studio.Login.Pages.Login.Login.TryLogin()
at Elsa.Studio.Components.StudioComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
at Elsa.Studio.Components.StudioComponentBase.InvokeWithBlazorServiceContext(Func`1 func)
at Microsoft.AspNetCore.Components.Forms.EditForm.HandleSubmitAsync()
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState)
Microsoft.AspNetCore.Components.Server.Circuits.CircuitHost: Error: Unhandled exception in circuit 'd6-nJm9fFXPt3LK-GaQ0Io24RKX-OsV2eQ8qcVJa0gQ'.
```

I have also tried to copy the code directly from the docs, but same result.

Start in src/installation/elsa-studio/ElsaStudioBlazorServer, checking the sample's appsettings.json and project dependencies against the applicationUrl values described in the issue. Run the sample through the login flow and trace the configured backend request; done means the sample builds with its required packages and login no longer produces connection or 400 errors.

Written by the indexing model from the issue text.