server(fix[raise_if_dead]): suppress check_call stdout/stderr

why: subprocess.check_call without stdout/stderr redirection inherits the
     parent process's file descriptors, printing tmux output directly to
     the terminal. Library code should not produce terminal noise.
what:
- Pass stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL to check_call

Author: tony

src/libtmux/server.py

@@ -247,7 +247,11 @@ def raise_if_dead(self) -> None:
             cmd_args.insert(0, f"-f{self.config_file}")
 
         try:
-            subprocess.check_call([resolved, *cmd_args])
+            subprocess.check_call(
+                [resolved, *cmd_args],
+                stdout=subprocess.DEVNULL,
+                stderr=subprocess.DEVNULL,
+            )
         except FileNotFoundError:
             raise exc.TmuxCommandNotFound from None