<!--- Verify first that your issue is not already reported on GitHub -->
<!--- Also test if the latest release and devel branch are affected too -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
If you don't have an ssh client installed in container image or on your system, ansible just throws following error -  `The error was: FileNotFoundError: [Errno 2] No such file or directory: b'ssh': b'ssh'` error. 

```
TASK [Gathering Facts] *********************************************************
[WARNING]: Unhandled error in Python interpreter discovery for host <hostname1>: [Errno 2] No such file or directory: b'ssh': b'ssh'

[WARNING]: Unhandled error in Python interpreter discovery for host <hostname2>: [Errno 2] No such file or directory: b'ssh': b'ssh'

An exception occurred during task execution. To see the full traceback, use -vvv. The error was: FileNotFoundError: [Errno 2] No such file or directory: b'ssh': b'ssh'
fatal: [<hostname1>]: FAILED! => {"msg": "Unexpected failure during module execution.", "stdout": ""}

An exception occurred during task execution. To see the full traceback, use -vvv. The error was: FileNotFoundError: [Errno 2] No such file or directory: b'ssh': b'ssh'
fatal: [<hostname2>]: FAILED! => {"msg": "Unexpected failure during module execution.", "stdout": ""}
```

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
2.9.6
```

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
Run playbook on the system where ssh client is not installed & playbook is expecting to use ssh keys for remote hosts.


<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
If possible adding an error message indicating `ssh client is not installed on the system`

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
Error message mentioned in the summary 
The error was: FileNotFoundError: [Errno 2] No such file or directory: b'ssh': b'ssh'
```

Thank you!!
if command == b'sshpass':
        
        if return_tuple[0] == 5:
            msg = 'Invalid/incorrect username/password. Skipping remaining {0} retries to prevent account lockout:'.format(remaining_retries)
            if remaining_retries <= 0:
                msg = 'Invalid/incorrect password:'
            if no_log:
                msg = '{0} <error censored due to no log>'.format(msg)
            else:
                msg = '{0} {1}'.format(msg, to_native(return_tuple[2]).rstrip())
            raise AnsibleAuthenticationFailure(msg)
        
        
        
        elif return_tuple[0] in [1, 2, 3, 4, 6]:
            msg = 'sshpass error:'
            if no_log:
                msg = '{0} <error censored due to no log>'.format(msg)
            else:
                details = to_native(return_tuple[2]).rstrip()
                if "sshpass: invalid option -- 'P'" in details:
                    details = 'Installed sshpass version does not support customized password prompts. ' \
                              'Upgrade sshpass to use sshpass_prompt, or otherwise switch to ssh keys.'
                    raise AnsibleError('{0} {1}'.format(msg, details))
                msg = '{0} {1}'.format(msg, details)
    if return_tuple[0] == 255:
        SSH_ERROR = True
        for signature in b_NOT_SSH_ERRORS:
            if signature in return_tuple[1]: