Fix problems in handling of CLI "exec" mode and "config" mode commands with prompts.

[kerry-meyer]

Root cause analysis:

Commands containing a "prompt/answer" sequence require
the user to specify a dictionary containing the command, prompt,
and "answer" (for the prompt). The previously existing handling enclosed the
entire command dictionary (containing the "command", "prompt",
and "answer" key/value pairs) in quotes as the value for an
unintended outer "command" key. The other items in the
dictionary input to the "send_command" API (for sending
commands to a device) were set to defaults (for exec commands)
or left unspecified (for configuration commands).

For example:

• Ansible "module" contents from parsing a playbook that specified
  an exec command "list" containing a single command/prompt/answer sequence:

---

["{'command': 'image remove all', 'prompt': '\\[y/N\\]:', 'answer': 'N'}"]

• Incorrect result of formatting the "raw" single command list shown
  above to prepare for invoking the "send_command" API:

---

{'command': "{'command': 'image remove all', 'prompt': '\\[y/N\\]:', 'answer': 'N'}", 'output': None, 'prompt': None, 'answer': None, 'newline': True, 'sendonly': False, 'check_all': False}

• Instead of the incorrect dictionary shown above, the desired dictionary
  is:

---

{'command': 'image remove all', 'prompt': '\\[y/N\\]:', 'answer': 'N', 'newline': True, 'sendonly': False, 'check_all': False}

Fix:

- Create a utility function to generate the correct dictionary
entries from the input command list parsed from the user
playbook.
- Use the resulting dictionary instead of the "raw" list
of quoted command strings provided by the "AnsibleModule"
parsing invocation to formulate the correct arguments
for the "send_command" API.
- (sonic-config test suite only): Fix problems preventing execution of sonic-config test cases:
    - Change the names for snmp community list entries to valid names.
    - Use /tmp directory instead of /home directory to avoid a permissions failure for
        the "backup" test.

SUMMARY

ISSUE TYPE

• Bugfix Pull Request

COMPONENT NAME

sonic_command, sonic_cli

ADDITIONAL INFORMATION

Unit and Regression Test Results:

• sonic-config test suite output comparison before and after the fix: (The Failing "prompt_test_case" was removed for the base comparison because it aborted the test suite. That test passes with the fix.)

prompt_fix_sonic_command_regression_comparison.txt

• Base regression test result
  prompt_fix_PR_regression-base-2022-04-21-23-29-14.pdf

• Fix regression test results (The port breakout test was re-run after editing the selected ports to match the
  switch configuration.)
  prompt_fix_PR_regression-2022-04-22-00-35-17.pdf
  prompt_fix_PR_port_breakout_regression-2022-04-22-14-22-30.pdf

[stalabi1]

I approve of these changes.