Integration Tests using XUnit.NET - Solution root could not be located using application root

I have two projects in the solution.

1. Web API using .NET Core 3.1
2. Integration Tests using XUnit.NET and .NET Core 3.1, this project has a reference to Web API project

A sample integration test class is here.

public class CustomersControllerTests : IClassFixture<WebApplicationFactory<WebAPIProject.Startup>>  
{  
        public CustomersControllerTests(WebApplicationFactory<WebAPIProject.Startup> factory)  
        {  
            _httpClient = factory.CreateClient();  
            _clusterRepository = factory.Services.GetService<IClusterRepository>();              
        }  
}  

	  

I developed the integration tests using the following article.

https://video2.skills-academy.com/en-us/aspnet/core/test/integration-tests?view=aspnetcore-3.1

All tests ran fine in Visual Studio. So the integration tests project is put into a Azure DevOps pipeline.
Here are the tasks in the Agent job.

1. Download Pipeline Artifacts task (to download the build artifacts from build pipeline)
2. Visual Studio test platfrom installer task
3. Visual Studio Test task

All tests are failed during execution and here is the stack trace for one of the tests.

System.InvalidOperationException : Solution root could not be located using application root D:\a\r1\a\_ReleaseManagement.API.IntegrationTests-CI\drop\ReleaseManagement.IntegrationTests\Release\.  
[xUnit.net 00:00:06.59]       Stack Trace:  
at Microsoft.AspNetCore.TestHost.WebHostBuilderExtensions.UseSolutionRelativeContentRoot(IWebHostBuilder builder, String solutionRelativePath, String applicationBasePath, String solutionName)  
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.SetContentRoot(IWebHostBuilder builder)  
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.<EnsureServer>b__20_0(IWebHostBuilder webHostBuilder)  
at Microsoft.Extensions.Hosting.GenericHostWebHostBuilderExtensions.ConfigureWebHost(IHostBuilder builder, Action`1 configure)  
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.EnsureServer()  
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.CreateDefaultClient(DelegatingHandler[] handlers)  
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.CreateDefaultClient(Uri baseAddress, DelegatingHandler[] handlers)  
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.CreateClient(WebApplicationFactoryClientOptions options)  
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.CreateClient()  
/home/vsts/work/1/s/src/UnitTests/ReleaseManagement.IntegrationTests/Api/CustomersControllerTests.cs(29,0): at ReleaseManagement.IntegrationTests.Api.CustomersControllerTests..ctor(WebApplicationFactory`1 factory)  
2020-11-27T09:54:43.4381123Z ##[error][xUnit.net 00:00:06.59]     ReleaseManagement.IntegrationTests.Api.CustomersControllerTests.CreateCustomer_Success [FAIL]  

Any help on how to resolve this issue so the tests can be executed in azure devops pipeline?