[enabler][zos_copy]Add_error_message

[AndreMarcel99]

SUMMARY

Add validation for source members that does not exist
Fixes #1010

ISSUE TYPE

• Enabler Pull Request

ADDITIONAL INFORMATION

Add extra validation for any source member that does not exist

TASK [Execute a copy expecting to fail] *************************************************************************************************************************************************************
fatal: [zvm]: FAILED! => {"changed": false, "msg": "Unable to execute copy. Source member does not exist MEMBER.", "rc": null, "stderr": null, "stderr_lines": null, "stdout": null, "stdout_lines": null}