fix 'doas' become_method support, previously committed patch not submitted to devel branch (#37511)

* fix become_method 'doas' support by properly specifying becomecmd

a repatch of https://github.com/ansible/ansible/pull/13451/ which was never committed to 'devel' branch.

* fix play_context test for become_method doas to match new becomecmd

lib/ansible/playbook/play_context.py

@@ -544,7 +544,7 @@ class PlayContext(Base):
                     flags += ' -u %s ' % self.become_user
 
                 # FIXME: make shell independent
-                becomecmd = '%s %s echo %s && %s %s env ANSIBLE=true %s' % (exe, flags, success_key, exe, flags, cmd)
+                becomecmd = '%s %s %s -c %s' % (exe, flags, executable, success_cmd)
 
             elif self.become_method == 'dzdo':