fix(jans-cli): `--schema` option should be renamed to `--schema-sample`

[ossdhaval]

Describe the bug
Reference chat thread here

jans-cli provides a switch --schema to fetch the schema associated with the operation. For example,

/opt/jans/jans-cli/config-cli.py --schema JansAttribute

What is actually returned as the response is a sample of the associated schema, i.e keys with values as per schema. Sample can be used by the administrator directly to perform the operation.

Since the --schema is not returning the schema but a sample, proposal here is to rename the option as --schema-sample