Fix linting issues in MCP tool registration tests

- Remove unused httpx import
- Remove unused mock_mcp_tool variable assignments
- Sort imports properly
- Remove trailing whitespace from blank lines

Author: JosinaJoy

tests/tooling/extensions/agentframework/services/test_mcp_tool_registration_service.py

@@ -12,10 +12,9 @@
 errors when calling MCP tool servers.
 """
 
-from unittest.mock import AsyncMock, Mock, patch, MagicMock
-import pytest
-import httpx
+from unittest.mock import AsyncMock, MagicMock, Mock, patch
 
+import pytest
 from microsoft_agents_a365.tooling.extensions.agentframework.services import (
     McpToolRegistrationService,
 )
@@ -92,7 +91,7 @@ async def test_httpx_client_has_authorization_header(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.httpx.AsyncClient"
         ) as mock_httpx_client, patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.MCPStreamableHTTPTool"
-        ) as mock_mcp_tool, patch(
+        ), patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.ChatAgent"
         ), patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.Utility.resolve_agent_identity",
@@ -145,7 +144,7 @@ async def test_httpx_client_has_user_agent_header(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.httpx.AsyncClient"
         ) as mock_httpx_client, patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.MCPStreamableHTTPTool"
-        ) as mock_mcp_tool, patch(
+        ), patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.ChatAgent"
         ), patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.Utility.resolve_agent_identity",
@@ -196,7 +195,7 @@ async def test_httpx_client_has_correct_timeout(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.httpx.AsyncClient"
         ) as mock_httpx_client, patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.MCPStreamableHTTPTool"
-        ) as mock_mcp_tool, patch(
+        ), patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.ChatAgent"
         ), patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.Utility.resolve_agent_identity",
@@ -236,7 +235,7 @@ async def test_mcp_tool_receives_http_client_not_headers(
         mock_mcp_server_config,
     ):
         """Test that MCPStreamableHTTPTool is instantiated with http_client parameter.
-        
+
         This is the critical test that prevents regression to the bug where
         headers were passed directly to MCPStreamableHTTPTool and silently ignored.
         The fix passes an httpx.AsyncClient with pre-configured headers instead.
@@ -307,7 +306,7 @@ async def test_httpx_client_added_to_internal_list_for_cleanup(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.httpx.AsyncClient"
         ) as mock_httpx_client, patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.MCPStreamableHTTPTool"
-        ) as mock_mcp_tool, patch(
+        ), patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.ChatAgent"
         ), patch(
             "microsoft_agents_a365.tooling.extensions.agentframework.services.mcp_tool_registration_service.Utility.resolve_agent_identity",
@@ -388,7 +387,7 @@ async def test_cleanup_handles_client_close_errors_gracefully(self, service):
 
 class TestHttpxClientLifecycle:
     """End-to-end tests for httpx client lifecycle management.
-    
+
     These tests verify that clients created during add_tool_servers_to_agent()
     are properly tracked and cleaned up by cleanup(), preventing connection
     and file descriptor leaks.
@@ -437,7 +436,7 @@ async def test_full_client_lifecycle_single_server(
         mock_chat_client,
     ):
         """Test full lifecycle: create client via add_tool_servers, then cleanup.
-        
+
         This end-to-end test ensures that:
         1. add_tool_servers_to_agent() creates and tracks httpx clients
         2. cleanup() calls aclose() on each tracked client
@@ -504,7 +503,7 @@ async def test_full_client_lifecycle_multiple_servers(
         mock_chat_client,
     ):
         """Test lifecycle with multiple MCP servers creating multiple clients.
-        
+
         Verifies that when multiple tool servers are configured, each gets its
         own httpx client that is properly tracked and cleaned up.
         """
@@ -578,7 +577,7 @@ async def test_full_client_lifecycle_multiple_servers(
     @pytest.mark.unit
     async def test_cleanup_idempotent_no_clients(self, service):
         """Test that cleanup() is safe to call when no clients exist.
-        
+
         Ensures cleanup doesn't raise errors when called on a fresh service
         or called multiple times.
         """
@@ -605,7 +604,7 @@ async def test_cleanup_called_twice_after_creating_clients(
         mock_chat_client,
     ):
         """Test that calling cleanup() twice doesn't cause issues.
-        
+
         After the first cleanup, the list is cleared, so the second cleanup
         should be a no-op without errors.
         """