[FLINK-33117][docs] Fix scala example for NamedParameterClass

[snuyanzin]

What is the purpose of the change

This is a follow up for the comment #25833 (comment)

Brief change log

udfs docs example for NamedParameterClass

Verifying this change

just docs examples (paste to scala)

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): ( no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): ( no)
• The serializers: (no)
• The runtime per-record code paths (performance sensitive): (no)
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (no)
• The S3 file system connector: (no)

Documentation

• Does this pull request introduce a new feature? ( no)
• If yes, how is the feature documented? (docs )

[flinkbot]

CI report:

• 93fa9ed Azure: SUCCESS

Bot commands

The @flinkbot bot supports the following commands:

• @flinkbot run azure re-run the last Azure build

[snuyanzin]

@flinkbot run azure

[liuyongvs]

LGTM +1