Refactor test files for improved readability and consistency

- Removed unnecessary blank lines and adjusted formatting in test files.
- Ensured consistent use of commas in function calls and assertions across various test cases.
- Updated import statements for better organization and clarity.
- Enhanced mock setups in tests for better isolation and reliability.
- Improved assertions to follow a consistent style for better readability.

tests/api/v1/test_socket_endpoints.py

@@ -158,7 +158,7 @@ class TestSocketEndpoints:
 
     @pytest.mark.asyncio
     async def test_send_message_missing_parameters(
-        self, authenticated_client: AsyncClient, authenticated_user: User
+        self, authenticated_client: AsyncClient, authenticated_user: User,
     ):
         """Test sending message with missing parameters."""
         # Missing target_user_id
@@ -177,7 +177,7 @@ class TestSocketEndpoints:
 
     @pytest.mark.asyncio
     async def test_broadcast_message_missing_parameters(
-        self, authenticated_client: AsyncClient, authenticated_user: User
+        self, authenticated_client: AsyncClient, authenticated_user: User,
     ):
         """Test broadcasting message with missing parameters."""
         response = await authenticated_client.post("/api/v1/socket/broadcast")
@@ -185,7 +185,7 @@ class TestSocketEndpoints:
 
     @pytest.mark.asyncio
     async def test_send_message_invalid_user_id(
-        self, authenticated_client: AsyncClient, authenticated_user: User
+        self, authenticated_client: AsyncClient, authenticated_user: User,
     ):
         """Test sending message with invalid user ID."""
         response = await authenticated_client.post(