[hotfix][codestyle] Refactor equals for StreamRecord

[satybald]

What is the purpose of the change

Removing nested IFs for StreamRecord#equals method without changing the comparison logic.

Brief change log

• refactors StreamRecord#equals method

Verifying this change

This change is already covered by existing tests, such as StreamRecordTest.

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, Yarn/Mesos, 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? (not applicable)

[StephanEwen]

Thank you joining the Flink community and contributing.

Considering this specific change: I would like to not merge this change.

There was nothing wrong with the original code - this is a cosmetic change that does not actually change anything significant. I personally would like to encourage not doing such changes, because a project can easily get into a situation where committers spend a significant amount of time formatting code and style back and forth rather than working on issues for noticeable improvements.

I would encourage you to look at the "how to contribute" page, which describes how to find interesting issues for new contributions.

[satybald]

thanks for the feedback @StephanEwen