optimize obtaining event-loop down to 1 line

Author: Vizonex

src/aiohappyeyeballs/impl.py

@@ -51,8 +51,8 @@ async def start_connection(
             transport, protocol = await loop.create_connection(
                 MyProtocol, sock=socket, ...)
     """
-    if not (current_loop := loop):
-        current_loop = asyncio.get_running_loop()
+    
+    current_loop = loop or asyncio.get_running_loop()
 
     single_addr_info = len(addr_infos) == 1