Re-add support for setting shell from play context (#52139)

* Re-add support for setting shell from play context

* Add integration tests

* Add more tests for shell override

* fix sanity issue

test/integration/targets/shell/action_plugins/test_shell.py

@@ -0,0 +1,19 @@
+# This file is part of Ansible
+
+# Copyright (c) 2019 Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+# Make coding more python3-ish
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+from ansible.plugins.action import ActionBase
+
+
+class ActionModule(ActionBase):
+
+    def run(self, tmp=None, task_vars=None):
+        result = super(ActionModule, self).run(tmp, task_vars)
+        del tmp  # tmp no longer has any effect
+        result['shell'] = self._connection._shell.SHELL_FAMILY
+        return result