win_psexec: added the pid return value to the docs (#50664)

lib/ansible/modules/windows/win_psexec.py

@@ -149,6 +149,11 @@ cmd:
     returned: always
     type: str
     sample: psexec.exe -nobanner \\remote_server -u "DOMAIN\Administrator" -p "some_password" -accepteula E:\setup.exe
+pid:
+    description: The PID of the async process created by PsExec.
+    returned: when C(wait=False)
+    type: int
+    sample: 1532
 rc:
     description: The return code for the command.
     returned: always