cluster settings: `iceberg_rest_catalog_base_location` bucket should always be the same as `cloud_storage_bucket`

Issue 

When configuring Redpanda to use AWS Glue as the Iceberg REST catalog, you must set Redpanda config parameter iceberg_rest_catalog_base_location to an S3 URI 
so that AWS Glue knows where to store and find the Iceberg tables' data and metadata files. 

If you omit this property, the integration may not work as expected with AWS Glue or other REST catalogs that require it.

The  S3 bucket-name defined in  Redpanda config parameter iceberg_rest_catalog_base_location bucket must  always be the same bucket-name as the one  defined in config parameter  cloud_storage_bucket

It is not supported to have different buckets for these 2 config parameters..

If the iceberg_rest_catalog_base_location  is set to a different bucket to cloud_storage_bucket Redpanda will report these messages and fail to update Iceberg.

datalake - {kafka/iceberg-test/0} - record_multiplexer.cc:301 - Error getting location prefix for s3://redpanda-iceberg-storage-test-us/data//redpanda/iceberg-test while creating writer at offset 0

Workaround/Resolution 

A documentation bug has been filed to add this information.

Configure  iceberg_rest_catalog_base_location  so the bucket name is the same one that is defined in cloud_storage_bucket

e.g

s3:/bucket-name-defined-in-#cloud_storage_bucket/