REST API: cacheName is not an optional parameter

Hello, I have been reviewing the [Apache Ignite REST API documentation](https://ignite.apache.org/docs/latest/restapi) and noticed an inconsistency.

The cacheName parameter is optional for certain commands. However, when using the API, I found that the cacheName parameter is required in these cases. The documentation says: 'Cache name. If not provided, the default cache is used.'.

Steps to reproduce:

1. Attempt to send a request without the cacheName parameter.
2. Notice that the request fails and explicitly requires the cacheName parameter.

Regards.

Begin with the REST API documentation linked in the issue and reproduce a command without cacheName. Trace the corresponding REST API entry point to determine whether the implementation or documentation is inconsistent; done means the documented optional behavior and observed request handling agree, with a regression check if applicable.

Written by the indexing model from the issue text.