fix(data): add user hint to use template flag when unsupported json array is detected

[reubenmiller]

Since the --data flag currently does not support providing json arrays, provide a useful hint to users that they can just use the --template flag instead.

Below shows the error/hint shown to users.

$ c8y inventory create --data '["one"]' --dry

2025-02-16T19:58:58.857+0100    ERROR   commandError: invalid data type (array) provided on the 'data' flag. Currently only key/value or json objects are supported. Hint: Try using the 'template' flag instead

The above command can then be simply rewritten by replace --data with --template:

c8y inventory create --template '["one"]' --dry

Related to #432