Add Octops Fleet Garbage Collector project to third party docs

[danieloliveira079]

What type of PR is this?

Uncomment only one /kind <> line, press enter to put that in a new line, and remove leading whitespace from that line:

/kind breaking
/kind bug
/kind cleanup

/kind documentation

/kind feature
/kind hotfix
/kind release

What this PR does / Why we need it:
This PR adds the https://github.com/Octops/octops-fleet-gc project link to the list of Controllers under the Third Party section of the website.

This project was developed based on input from the community on Slack.

Which issue(s) this PR fixes:

Closes #

Special notes for your reviewer:

[agones-bot]

Build Succeeded 👏

Build Id: cc8ab40f-7983-4809-872d-1a9a9335d8e0

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:1.35.0-dev-7866e81-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-extensions:1.35.0-dev-7866e81-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.35.0-dev-7866e81-linux-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.35.0-dev-7866e81-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.35.0-dev-7866e81-amd64
• Linux C++ SDK (build): agonessdk-1.35.0-dev-7866e81-amd64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.35.0-dev-7866e81-amd64.zip

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

• https://7866e81-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/3359/head:pr_3359 && git checkout pr_3359
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.registry=us-docker.pkg.dev/agones-images/ci --set agones.image.tag=1.35.0-dev-7866e81-amd64

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: danieloliveira079, markmandel

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

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• OWNERS [markmandel]

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[google-oss-prow]

New changes are detected. LGTM label has been removed.

[agones-bot]

Build Succeeded 👏

Build Id: 673285f3-be10-4986-88ce-160e445a6827

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:1.35.0-dev-44225d3-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-extensions:1.35.0-dev-44225d3-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.35.0-dev-44225d3-linux-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.35.0-dev-44225d3-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.35.0-dev-44225d3-amd64
• Linux C++ SDK (build): agonessdk-1.35.0-dev-44225d3-amd64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.35.0-dev-44225d3-amd64.zip

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

• https://44225d3-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/3359/head:pr_3359 && git checkout pr_3359
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.registry=us-docker.pkg.dev/agones-images/ci --set agones.image.tag=1.35.0-dev-44225d3-amd64