chore: adapt boolean schema cherry-picks to v2 branch

Remove references to OpenApi3_2 version and Self property which don't exist
in the v2 support branch. Keep only v2.0, v3.0, and v3.1 support in tests.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: baywet

test/Microsoft.OpenApi.Readers.Tests/V31Tests/OpenApiDocumentTests.cs

@@ -612,25 +612,6 @@ public async Task ValidateReferencedExampleInSchemaWorks()
             Assert.Empty(result.Diagnostic.Warnings);            
         }
 
-        [Fact]
-        public async Task ParseDocumentWithSelfExtensionWorks()
-        {
-            // Arrange && Act
-            var path = Path.Combine(SampleFolderPath, "documentWithSelfExtension.yaml");
-            var result = await OpenApiDocument.LoadAsync(path, SettingsFixture.ReaderSettings);
-
-            // Assert
-            Assert.NotNull(result.Document);
-            Assert.NotNull(result.Document.Self);
-            Assert.Equal("https://example.org/api/openapi.yaml", result.Document.Self.ToString());
-            Assert.Equal("API with x-oai-$self extension", result.Document.Info.Title);
-            Assert.Equal("1.0.0", result.Document.Info.Version);
-            // The x-oai-$self extension should be moved to the Self property and not remain in extensions
-            Assert.Null(result.Document.Extensions);
-            Assert.Empty(result.Diagnostic.Errors);
-            Assert.Empty(result.Diagnostic.Warnings);
-        }
-
         [Fact]
         public void LoadDocumentWithBooleanSchemaShouldNotThrowNullReferenceException()
         {

test/Microsoft.OpenApi.Tests/Models/OpenApiSchemaTests.cs

@@ -208,7 +208,6 @@ public class OpenApiSchemaTests
         [InlineData(OpenApiSpecVersion.OpenApi2_0)]
         [InlineData(OpenApiSpecVersion.OpenApi3_0)]
         [InlineData(OpenApiSpecVersion.OpenApi3_1)]
-        [InlineData(OpenApiSpecVersion.OpenApi3_2)]
         public async Task SerializeBasicSchemaAsJsonWorks(OpenApiSpecVersion version)
         {
             // Arrange