[FLINK-37438] Improve the createLocalEnvironment by reduce duplicate operation on Configuration

[beliefer]

What is the purpose of the change

This PR proposes to improve the createLocalEnvironment by reduce duplicate operation on Configuration.

Brief change log

Improve the createLocalEnvironment by reduce duplicate operation on Configuration
Currently, StreamExecutionEnvironment provides a createLocalEnvironment with one parameter parallelism.

    public static LocalStreamEnvironment createLocalEnvironment(int parallelism) {
        return createLocalEnvironment(parallelism, new Configuration());
    }

Above method will create a new instance of Configuration and then calling the below override one.

    public static LocalStreamEnvironment createLocalEnvironment(
            int parallelism, Configuration configuration) {
        Configuration copyOfConfiguration = new Configuration();
        copyOfConfiguration.addAll(configuration);
        copyOfConfiguration.set(CoreOptions.DEFAULT_PARALLELISM, parallelism);
        return createLocalEnvironment(copyOfConfiguration);
    }

The second will create another instance of Configuration and name it with copyOfConfiguration.
You can see add configuration into copyOfConfiguration with addAll.
The issue is create Configuration duplicately and an extra operation addAll.

Verifying this change

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

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:

• 6c06483 Azure: SUCCESS

Bot commands

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

[beliefer]

ping @1996fanrui cc @davidradl

[davidradl]

nit: Or
return createLocalEnvironment(new Configuration().set(CoreOptions.DEFAULT_PARALLELISM, parallelism));

[beliefer]

@davidradl @1996fanrui
Does Flink have any coding style preferences for this style?

[davidradl]

@beliefer I found https://flink.apache.org/how-to-contribute/code-style-and-quality-java/ but it does not include this example.

I was only thinking to not define variables if we can avoid it. As the committer @1996fanrui WDYT?

[1996fanrui]

Does Flink have any coding style preferences for this style?

I didn't see the strict style preference for this case. I like @davidradl 's suggestion because we could avoid one temporary variable.

[beliefer]

Done.

[1996fanrui]

Thanks for the refactor!

LGTM

[1996fanrui]

Hi @davidradl , do you have any comment about this PR?

I will merge it next Monday if no more comment.

[beliefer]

@1996fanrui @davidradl Thank you all!