[FLINK-8933] Avoid calling Class#newInstance(part 1)

[yanghua]

What is the purpose of the change

This pull request avoid calling Class#newInstance

Brief change log

• replaced Class#newInstance to Class#getDeclaredConstructor#newInstance()

Verifying this change

This change is already covered by existing tests*.

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): (yes / no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): (yes / no)
• The serializers: (yes / no / don't know)
• The runtime per-record code paths (performance sensitive): (yes / no / don't know)
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Yarn/Mesos, ZooKeeper: (yes / no / don't know)
• The S3 file system connector: (yes / no / don't know)

Documentation

• Does this pull request introduce a new feature? (yes / no)
• If yes, how is the feature documented? (not applicable / docs / JavaDocs / not documented)

[yanghua]

cc @zentol splitted it into two PRs please review and apologize to you again

[zentol]

+1

[StephanEwen]

Similar as to #6016: Should we close this PR until we have consensus whether we want to change this?

Especially the performance implications in methods/classes on the "hot code paths" makes this a tricky change...

[yanghua]

OK, agree, closing this PR~