add Vela Games to companies that use Agones

[comerford]

What type of PR is this?
/kind documentation

What this PR does / Why we need it:

Spotted an addition in #2002 so wanted to add Vela Games also (having gotten internal approval to do so)

Special notes for your reviewer:

Basically copied #2002 and local build looked fine - if anything different is required, just let me know

[agones-bot]

Build Succeeded 👏

Build Id: a2973ba7-93e4-46f6-8ee9-45a33671355d

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

• image: gcr.io/agones-images/agones-controller:1.13.0-1b5b1dd
• image: gcr.io/agones-images/agones-sdk:1.13.0-1b5b1dd
• image: gcr.io/agones-images/agones-ping:1.13.0-1b5b1dd
• Linux C++ SDK (build): agonessdk-1.13.0-1b5b1dd-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.13.0-1b5b1dd.zip

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

• https://1b5b1dd-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/2003/head:pr_2003 && git checkout pr_2003
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.13.0-1b5b1dd

[markmandel]

Thank you!

[google-oss-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• OWNERS [markmandel]

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