subprocess: Use _CMD instead of str | bytes in getstatusoutput and getoutput (#11354)

Author: n-takumasa

stdlib/subprocess.pyi

@@ -2564,12 +2564,12 @@ class Popen(Generic[AnyStr]):
 
 # The result really is always a str.
 if sys.version_info >= (3, 11):
-    def getstatusoutput(cmd: str | bytes, *, encoding: str | None = None, errors: str | None = None) -> tuple[int, str]: ...
-    def getoutput(cmd: str | bytes, *, encoding: str | None = None, errors: str | None = None) -> str: ...
+    def getstatusoutput(cmd: _CMD, *, encoding: str | None = None, errors: str | None = None) -> tuple[int, str]: ...
+    def getoutput(cmd: _CMD, *, encoding: str | None = None, errors: str | None = None) -> str: ...
 
 else:
-    def getstatusoutput(cmd: str | bytes) -> tuple[int, str]: ...
-    def getoutput(cmd: str | bytes) -> str: ...
+    def getstatusoutput(cmd: _CMD) -> tuple[int, str]: ...
+    def getoutput(cmd: _CMD) -> str: ...
 
 def list2cmdline(seq: Iterable[StrOrBytesPath]) -> str: ...  # undocumented