ssh_authorzed_key: Fix invalid 'options' error

ssh_authorzed_key: Fix invalid 'options' error

Prior to this, the example of a valid "options" value for the
ssh_authorized_key type was syntactically incorrect; it did not include
the closing single quote.

Example of incorrect error message:

```
Error: Parameter options failed on Ssh_authorized_key[testkey]: Option from=foo.com is not valid. A single option must either be of the form 'option' or 'option="value". Multiple options must be provided as an array (file: /tmp/test.pp, line: 5)
```

After this, the error shows the correct syntax for specifying an option:

```
Error: Parameter options failed on Ssh_authorized_key[testkey]: Option from=foo.com is not valid. A single option must either be of the form 'option' or 'option="value"'. Multiple options must be provided as an array (file: /tmp/test.pp, line: 5)
```