Add extensive integration and unit tests for APIs and utilities

- Introduced new integration tests for `HolidayApi`, `InfoApi`, and other API endpoints.
- Improved testing consistency by standardizing `CustomWebApplicationFactory` configuration.
- Added utility tests for `DateOnlyJsonConverter`, `StringExtensions`, and `PaginationModel`.
- Updated dependencies in `api.Tests.csproj` for testing frameworks and libraries.
- Standardized `namespace` declarations and refactored redundant constructors across integration tests.

Author: Mteheran

api.Tests/ApiRoutesTests/AirportApiIntegrationTests.cs

@@ -1,7 +1,9 @@
-using api.Models;
 using System.Net.Http.Json;
+using api.Models;
 using api.Utils;
 
+namespace api.Tests.ApiRoutesTests;
+
 public class AirportApiIntegrationTests : IClassFixture<CustomWebApplicationFactory>
 {
     private readonly HttpClient _client;

api.Tests/ApiRoutesTests/CategoryNaturalAreaApiIntegrationTests.cs

@@ -1,14 +1,11 @@
 using System.Net.Http.Json;
 using api.Models;
 
+namespace api.Tests.ApiRoutesTests;
+
 public class CategoryNaturalAreaApiIntegrationTests : IClassFixture<CustomWebApplicationFactory> , IDisposable
 {
-    private readonly HttpClient _client;
-
-    public CategoryNaturalAreaApiIntegrationTests()
-    {
-       _client = new CustomWebApplicationFactory().CreateClient(); 
-    }
+    private readonly HttpClient _client = new CustomWebApplicationFactory().CreateClient();
 
     public void Dispose()
     {

api.Tests/ApiRoutesTests/CityApiIntegrationTests.cs

@@ -2,6 +2,8 @@
 using api.Models;
 using api.Utils;
 
+namespace api.Tests.ApiRoutesTests;
+
 public class CityApiIntegrationTests : IClassFixture<CustomWebApplicationFactory> , IDisposable
 {
     private readonly HttpClient _client;

api.Tests/ApiRoutesTests/ConstitutionArticleApiIntegrationTests.cs

@@ -2,14 +2,11 @@
 using api.Models;
 using api.Utils;
 
+namespace api.Tests.ApiRoutesTests;
+
 public class ConstitutionArticleApiIntegrationTests : IClassFixture<CustomWebApplicationFactory>, IDisposable
 {
-    private readonly HttpClient _client;
-
-    public ConstitutionArticleApiIntegrationTests()
-    {
-       _client = new CustomWebApplicationFactory().CreateClient(); 
-    }
+    private readonly HttpClient _client = new CustomWebApplicationFactory().CreateClient();
 
     public void Dispose()
     {
@@ -105,4 +102,4 @@ public async Task GetConstitutionArticlesByChapterNumber_ReturnsOkWithChapterDat
         Assert.Equal(2, result.Count);
         Assert.All(result, article => Assert.Equal(chapterNumber, article.ChapterNumber));
     }
-}
+}

api.Tests/ApiRoutesTests/CountryApiIntegrationTests.cs

@@ -1,14 +1,12 @@
-using api.Models;
 using System.Net.Http.Json;
+using api.Models;
 
-public class CountryApiIntegrationTests : IClassFixture<CustomWebApplicationFactory>
-{
-    private readonly HttpClient _client;
+namespace api.Tests.ApiRoutesTests;
 
-    public CountryApiIntegrationTests(CustomWebApplicationFactory factory)
-    {
-        _client = factory.CreateClient();  
-    }
+public class CountryApiIntegrationTests(CustomWebApplicationFactory factory)
+    : IClassFixture<CustomWebApplicationFactory>
+{
+    private readonly HttpClient _client = factory.CreateClient();
 
     [Fact]
     public async Task GetCountry_ReturnsAllCountryData()
@@ -26,4 +24,4 @@ public async Task GetCountry_ReturnsAllCountryData()
         Assert.Equal("$", result.CurrencySymbol);
         Assert.Equal("Peso", result.Currency);
     }
-}
+}