Fix argument handling

[rsommer]

The key part of the argument handling has to be right after args, otherwise you'd get an AttributeError when trying to call encode on the args object.

Traceback (most recent call last):
  File "/tmp/tmp.VR4pSjeDta/vsphere-automation-sdk-python/samples/vsphere/vcenter/certificatemanagement/replace_tls_certificate.py", line 63, in <module>
    key = args.encode(encoding='utf-8').key.decode('unicode_escape')
AttributeError: 'Namespace' object has no attribute 'encode'

[vmwclabot]

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• Commit adfb526681600e71a06a0e66d84c5dd1d2307934 must be signed by [email protected]