[FLINK-37544] Replace Timer with single thread scheduled executor for BlobServer

[beliefer]

What is the purpose of the change

This PR aims to replace Timer with single thread scheduled executor for BlobServer.
The javadoc recommends ScheduledThreadPoolExecutor instead of Timer.

This change based on the following two points.
System time sensitivity

Timer scheduling is based on the absolute time of the operating system and is sensitive to the operating system's time. Once the operating system's time changes, Timer scheduling is no longer precise.
The scheduled Thread Pool Executor scheduling is based on relative time and is not affected by changes in operating system time.

Are anomalies captured

Timer does not capture exceptions thrown by Timer Tasks, and in addition, Timer is single threaded. Once a scheduling task encounters an exception, the entire thread will terminate and other tasks that need to be scheduled will no longer be executed.
The scheduled Thread Pool Executor implements scheduling functions based on a thread pool. After a task throws an exception, other tasks can still execute normally.

Brief change log

Replace Timer with single thread scheduled executor for BlobServer

Verifying this change

This change is already covered by existing tests, such as (BlobCacheCleanupTest, BlobServerCleanupTest and so on).

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:

• 463fd45 Azure: SUCCESS

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[beliefer]

@flinkbot run azure

[beliefer]

ping @NicoK cc @1996fanrui @davidradl @GOODBOY008

[davidradl]

@beliefer have you hit any issues with the current timer implementation? If not, I am reticent to change this area unless we are actually seeing issues here.

[beliefer]

Yes. I experienced the issue when using Timer.
You could refer apache/spark#44718