[FLINK-34227][runtime] Ensure that the scheduler close call doesn't leak IO threads into the JobMaster

[XComp]

What is the purpose of the change

This is a follow-up PR of #24489 based on @zentol 's comment. Check the PR #24489 for more context.

This PR focuses on fixing the IO thread leakage on the SchedulerNG side.

Brief change log

• Introduces new FutureUtils method for an async compose.
• Make checkpointsCleaner operation complete in the main thread for AdaptiveScheduler and SchedulerBase

Verifying this change

• Adds test method to AdaptiveSchedulerTest, DefaultSchedulerTest and AdaptiveBatchSchedulerTest

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: yes
• 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

[flinkbot]

CI report:

• 04a3dca Azure: FAILURE

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