public class IntegrationTestServer : IDisposable{
 public IntegrationTestServer()
        {           
            InitialiazeDataBases(); 
            InitializeIdentityServer();
            InitializeClientApi();
        }
          ......
}

[CollectionDefinition("IntegrationTestServer")]
public class DatabaseCollection : ICollectionFixture<IntegrationTestServer>
{
        // This class has no code, and is never created. Its purpose is simply
        // to be the place to apply [CollectionDefinition] and all the
        // ICollectionFixture<> interfaces.
}

[Collection("IntegrationTestServer")]
public class EventEntriesControllerIntegrationTest
{       
    private readonly IntegrationTestServer _fixtureServer;
    public EventEntriesControllerIntegrationTest(IntegrationTestServer fixtureServer)
   {
        _fixtureServer = fixtureServer;
   }
  
    [Fact]
    public async Task Should_RemoveEvent(){
       .....
    }
}