Revert "gh-128041: Add terminate_workers and kill_workers methods to ProcessPoolExecutor (GH-128043)" (#130838)

The test_concurrent_futures.test_process_pool test is failing in CI.

This reverts commit f97e4098ff.

Lib/concurrent/futures/process.py

@@ -626,14 +626,6 @@ class BrokenProcessPool(_base.BrokenExecutor):
     while a future was in the running state.
     """
 
-_TERMINATE = "terminate"
-_KILL = "kill"
-
-_SHUTDOWN_CALLBACK_OPERATION = {
-    _TERMINATE,
-    _KILL
-}
-
 
 class ProcessPoolExecutor(_base.Executor):
     def __init__(self, max_workers=None, mp_context=None,
@@ -863,66 +855,3 @@ class ProcessPoolExecutor(_base.Executor):
         self._executor_manager_thread_wakeup = None
 
     shutdown.__doc__ = _base.Executor.shutdown.__doc__
-
-    def _force_shutdown(self, operation):
-        """Attempts to terminate or kill the executor's workers based off the
-        given operation. Iterates through all of the current processes and
-        performs the relevant task if the process is still alive.
-
-        After terminating workers, the pool will be in a broken state
-        and no longer usable (for instance, new tasks should not be
-        submitted).
-        """
-        if operation not in _SHUTDOWN_CALLBACK_OPERATION:
-            raise ValueError(f"Unsupported operation: {operation!r}")
-
-        processes = {}
-        if self._processes:
-            processes = self._processes.copy()
-
-        # shutdown will invalidate ._processes, so we copy it right before
-        # calling. If we waited here, we would deadlock if a process decides not
-        # to exit.
-        self.shutdown(wait=False, cancel_futures=True)
-
-        if not processes:
-            return
-
-        for proc in processes.values():
-            try:
-                if not proc.is_alive():
-                    continue
-            except ValueError:
-                # The process is already exited/closed out.
-                continue
-
-            try:
-                if operation == _TERMINATE:
-                    proc.terminate()
-                elif operation == _KILL:
-                    proc.kill()
-            except ProcessLookupError:
-                # The process just ended before our signal
-                continue
-
-    def terminate_workers(self):
-        """Attempts to terminate the executor's workers.
-        Iterates through all of the current worker processes and terminates
-        each one that is still alive.
-
-        After terminating workers, the pool will be in a broken state
-        and no longer usable (for instance, new tasks should not be
-        submitted).
-        """
-        return self._force_shutdown(operation=_TERMINATE)
-
-    def kill_workers(self):
-        """Attempts to kill the executor's workers.
-        Iterates through all of the current worker processes and kills
-        each one that is still alive.
-
-        After killing workers, the pool will be in a broken state
-        and no longer usable (for instance, new tasks should not be
-        submitted).
-        """
-        return self._force_shutdown(operation=_KILL)