Backport PR to fix missing "changed" in net_get to stable-2.9

[saito-hideki]

SUMMARY

This PR is backporting request to fix net_get module does not initialize changed value. It will avoid to the following problem:

• Fixes Backport net_get from ansible.netcommon #74802

Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/ansible/executor/task_executor.py", line 147, in run
    res = self._execute()
  File "/usr/lib/python2.7/site-packages/ansible/executor/task_executor.py", line 665, in _execute
    result = self._handler.run(task_vars=variables)
  File "/usr/lib/python2.7/site-packages/ansible/plugins/action/net_get.py", line 94, in run
    result['changed'] = changed
UnboundLocalError: local variable 'changed' referenced before assignment
fatal: [192.168.100.100]: FAILED! => {
    "msg": "Unexpected failure during module execution.", 
    "stdout": ""
}

ISSUE TYPE

• Bugfix Pull Request

COMPONENT NAME

• net_get on stable-2.9

ADDITIONAL INFORMATION

N/A

[Akasurde]

@saito-hideki 2.9 is open for critical security fixes only. cc @sivel @relrod

[samdoran]

recheck