[fix](multi-catalog) when endpoint has no region, need a suggestion (#19203)
solve the problem
```
mysql> CREATE CATALOG iceberg PROPERTIES (
'type'='iceberg',
'iceberg.catalog.type'='rest',
'uri' = 'http://0.0.0.0:8888,
"AWS_ACCESS_KEY" = "admin",
"AWS_SECRET_KEY" = "password",
"AWS_REGION" = "us-east-1",
"AWS_ENDPOINT" = "http://minio:9000"
);
show databases;
ERROR 1105 (HY000): IllegalArgumentException, msg: java.lang.IllegalArgumentException: The value of property fs.s3a.endpoint.region must not be null
```
d006143330