[utils, etc] Kill child processes when yt-dl is killed

* derived from PR #26592, closes #26592

Authored by: Unrud

youtube_dl/compat.py

@@ -2890,6 +2890,7 @@ else:
     _terminal_size = collections.namedtuple('terminal_size', ['columns', 'lines'])
 
     def compat_get_terminal_size(fallback=(80, 24)):
+        from .utils import process_communicate_or_kill
         columns = compat_getenv('COLUMNS')
         if columns:
             columns = int(columns)
@@ -2906,7 +2907,7 @@ else:
                 sp = subprocess.Popen(
                     ['stty', 'size'],
                     stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-                out, err = sp.communicate()
+                out, err = process_communicate_or_kill(sp)
                 _lines, _columns = map(int, out.split())
             except Exception:
                 _columns, _lines = _terminal_size(*fallback)