Add agones4j to 3rd party libraries.

[portlek]

What type of PR is this?
/kind documentation

What this PR does / Why we need it:
added Infumia/agones4j to list of third party libraries. agones4j is a Client SDK written in Java to provide developers with ability to interact with Agones SDK.

[google-cla]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

For the most up to date status, view the checks section at the bottom of the pull request.

[agones-bot]

Build Failed 😱

Build Id: 2ea90bbf-fadc-404e-b859-e243808f9922

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[roberthbailey]

Flaky test in e2e-feature-gates:

--- FAIL: TestGameServerRestartBeforeReadyCrash (211.48s)
    gameserver_test.go:354: 
        	Error Trace:	gameserver_test.go:354
        	Error:      	Received unexpected error:
        	            	timed out waiting for the condition
        	Test:       	TestGameServerRestartBeforeReadyCrash

[roberthbailey]

@portlek - it looks like I can't pull your branch forward - can you rebase to head and re-push your branch?

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: portlek, roberthbailey

The full list of commands accepted by this bot can be found here.

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• OWNERS [roberthbailey]

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[google-oss-prow]

New changes are detected. LGTM label has been removed.

[portlek]

@roberthbailey done.

[agones-bot]

Build Succeeded 👏

Build Id: 66ab3110-7da7-46ce-8305-690199a588bc

The following development artifacts have been built, and will exist for the next 30 days:

• image: us-docker.pkg.dev/agones-images/ci/agones-controller:1.25.0-3fdbd60-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-controller:1.25.0-3fdbd60-arm64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.25.0-3fdbd60-linux-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.25.0-3fdbd60-linux-arm64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.25.0-3fdbd60-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.25.0-3fdbd60-arm64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.25.0-3fdbd60-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.25.0-3fdbd60-arm64
• Linux C++ SDK (build): agonessdk-1.25.0-3fdbd60-arm64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.25.0-3fdbd60-arm64.zip

A preview of the website (the last 30 builds are retained):

• https://3fdbd60-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/2656/head:pr_2656 && git checkout pr_2656
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.tag=1.25.0-3fdbd60-amd64

[roberthbailey]

Thanks!