[java] Add close method to JDK 11 client. Ensure close methods for Http client is called.

[pujagani]

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Description

Fixes #11270.

Motivation and Context

1. The memory leak is prominently seen when Augmenter is used which in turn creates a WebSocket connection using the HTTP Client to create a CDP connection. Though webdriver implementation supporting CDP does the same. The same client instance needs to be closed to ensure no resources are being held when the driver quits. The changes add the required code to achieve this.

2. Additionally, we supply an executor to the JDK 11 Http client for the worker threads, which is shutdown when the client is closed along with the underlying websocket. We also ensure there is no reference to the JDK 11 Http client instance after closing the client. This has helped fix the ever-increasing threads related to the JDK 11 Http client. HttpClientImpl (Java 11's implementation) does a timely check internally to see if no references to the client are there then closes the Selector Manager threads which are later collected when the GC kicks in.

The combination of the above 2 changes has helped ensure that there is no leak from JDK 11 Http client in different scenarios.

Before the changes:

After the changes:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[diemol]

We need to get the CI passing first though.

[pujagani]

Thank you for helping review. +1 , need to ensure CI tests run and it is all green.

[sonarcloud]

SonarCloud Quality Gate failed.   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
23.5% Duplication