[FLINK-36046] Change the existing org.apache.flink.streaming.api.functions.sink#DiscardingSink and org.apache.flink.streaming.api.functions.sink#PrintSinkFunction to use the new interfaces

[zhaomin1423]

What is the purpose of the change

Change the existing org.apache.flink.streaming.api.functions.sink#DiscardingSink and org.apache.flink.streaming.api.functions.sink#PrintSinkFunction to use the new interfaces

Brief change log

Verifying this change

This change is a trivial rework / code cleanup without any test coverage.

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)

[flinkbot]

CI report:

• d683438e484e88df78d5015f4754058d994702e2 Azure: FAILURE

Bot commands

The @flinkbot bot supports the following commands:

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

[zhaomin1423]

@flinkbot run azure

[github-actions[bot]]

This PR is being marked as stale since it has not had any activity in the last 90 days. If you would like to keep this PR alive, please leave a comment asking for a review. If the PR has merge conflicts, update it with the latest from the base branch.

If you are having difficulty finding a reviewer, please reach out to the community, contact details can be found here: https://flink.apache.org/what-is-flink/community/

If this PR is no longer valid or desired, please feel free to close it. If no activity occurs in the next 30 days, it will be automatically closed.

[github-actions[bot]]

This PR has been closed since it has not had any activity in 120 days. If you feel like this was a mistake, or you would like to continue working on it, please feel free to re-open the PR and ask for a review.