With this change, the `raw_arguments` and `raw_ssh_args` options are:
- STILL automatically converted as an Array when they are set a String
(no behaviour change)
- rejected if they are not of Array data type otherwise
Additional Notes:
- the 'as_array' tiny helper has been removed since it was no longer
used.
- there is for now no deeper validation (i.e. verifying that the Array
elements are only *String* objects)
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