Remove usage of Task.Delay in EventStore tests

[Alirexaa]

This could incur flakiness.

Aspire/tests/CommunityToolkit.Aspire.Hosting.EventStore.Tests/EventStoreFunctionalTests.cs

Line 135 in ea964f7

await Task.Delay(TimeSpan.FromSeconds(5));

Related dotnet/aspire#4878

[github-actions]

We have noticed this issue has not been updated within 21 days. If there is no action on this issue in the next 14 days, we will automatically close it. You can use /stale-extend to extend the window.

[Alirexaa]

/stale-extend