[FLINK-31324][connector] Make previous SingleThreadFetcherManager constructor deprecated

[Myasuka]

What is the purpose of the change

FLINK-28853 changed the default constructor of SingleThreadFetcherManager. Though the SingleThreadFetcherManager is annotated as Internal, it actually acts as some-degree public API, which is widely used in many connector projects:
flink-cdc-connector, flink-connector-mongodb and so on.

Once flink-1.17 is released, all these existing connectors are broken and cannot be used in new release version, and will throw exceptions like:

java.lang.NoSuchMethodError: org.apache.flink.connector.base.source.reader.fetcher.SingleThreadFetcherManager.<init>(Lorg/apache/flink/connector/base/source/reader/synchronization/FutureCompletingBlockingQueue;Ljava/util/function/Supplier;)V
	at com.ververica.cdc.connectors.mysql.source.reader.MySqlSourceReader.<init>(MySqlSourceReader.java:91) ~[flink-sql-connector-mysql-cdc-2.3.0.jar:2.3.0]
	at com.ververica.cdc.connectors.mysql.source.MySqlSource.createReader(MySqlSource.java:159) ~[flink-sql-connector-mysql-cdc-2.3.0.jar:2.3.0]
	at org.apache.flink.streaming.api.operators.SourceOperator.initReader(SourceOperator.java:312) ~[flink-dist-1.17-SNAPSHOT.jar:1.17-SNAPSHOT]
	at org.apache.flink.streaming.runtime.tasks.SourceOperatorStreamTask.init(SourceOperatorStreamTask.java:94) ~[flink-dist-1.17-SNAPSHOT.jar:1.17-SNAPSHOT]
	at org.apache.flink.streaming.runtime.tasks.StreamTask.restoreInternal(StreamTask.java:699) ~[flink-dist-1.17-SNAPSHOT.jar:1.17-SNAPSHOT]
	at org.apache.flink.streaming.runtime.tasks.StreamTask.restore(StreamTask.java:675) ~[flink-dist-1.17-SNAPSHOT.jar:1.17-SNAPSHOT]
	at org.apache.flink.runtime.taskmanager.Task.runWithSystemExitMonitoring(Task.java:952) ~[flink-dist-1.17-SNAPSHOT.jar:1.17-SNAPSHOT]
	at org.apache.flink.runtime.taskmanager.Task.restoreAndInvoke(Task.java:921) ~[flink-dist-1.17-SNAPSHOT.jar:1.17-SNAPSHOT]
	at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:745) ~[flink-dist-1.17-SNAPSHOT.jar:1.17-SNAPSHOT]
	at org.apache.flink.runtime.taskmanager.Task.run(Task.java:562) ~[flink-dist-1.17-SNAPSHOT.jar:1.17-SNAPSHOT]
	at java.lang.Thread.run(Thread.java:750) ~[?:1.8.0_362]

Thus, I suggest to make the original SingleThreadFetcherManager constructor as depreacted instead of removing it.

Brief change log

Introduce the previous constructor again and make it as deprecated.

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
• If yes, how is the feature documented? not applicable

[flinkbot]

CI report:

• 6abcd0b Azure: SUCCESS

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[wuchong]

LGTM.