refactor: improve code formatting and readability in group duty pin command and tests

- Enhanced the `pin_duty_cmd` function by improving code formatting for better readability, ensuring consistent style across the codebase.
- Updated unit tests for `pin_duty_cmd` to follow the same formatting improvements, enhancing clarity and maintainability.
- No functional changes were made; the focus was solely on code style and organization.

duty_teller/handlers/group_duty_pin.py

@@ -266,14 +266,18 @@ async def pin_duty_cmd(update: Update, context: ContextTypes.DEFAULT_TYPE) -> No
             )
             pinned = True
         except (BadRequest, Forbidden) as e:
-            logger.warning("Failed to pin message for pin_duty chat_id=%s: %s", chat_id, e)
+            logger.warning(
+                "Failed to pin message for pin_duty chat_id=%s: %s", chat_id, e
+            )
         await loop.run_in_executor(None, _sync_save_pin, chat_id, msg.message_id)
         next_end = await loop.run_in_executor(None, _get_next_shift_end_sync)
         await _schedule_next_update(context.application, chat_id, next_end)
         if pinned:
             await update.message.reply_text(t(lang, "pin_duty.pinned"))
         else:
-            await update.message.reply_text(t(lang, "pin_duty.could_not_pin_make_admin"))
+            await update.message.reply_text(
+                t(lang, "pin_duty.could_not_pin_make_admin")
+            )
         return
     try:
         await context.bot.pin_chat_message(