Unblock CI: Fix site link 404

[markmandel]

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

What this PR does / Why we need it:

This website for generating a self-signed SSL certificate is down, and also our instructions have since changed, so I removed the link altogether.

Which issue(s) this PR fixes:

N/A, but unblocks CI.

Special notes for your reviewer:

N/A

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

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

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

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [markmandel,roberthbailey]

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[agones-bot]

Build Succeeded 👏

Build Id: 1cf100c9-53d8-4c9c-83a7-f5ef9ca6ea5d

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

• image: gcr.io/agones-images/agones-controller:1.24.0-f5cfa4b-amd64
• image: gcr.io/agones-images/agones-controller:1.24.0-f5cfa4b-arm64
• image: gcr.io/agones-images/agones-ping:1.24.0-f5cfa4b-amd64
• image: gcr.io/agones-images/agones-ping:1.24.0-f5cfa4b-arm64
• Linux C++ SDK (build): agonessdk-1.24.0-f5cfa4b-arm64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.24.0-f5cfa4b-arm64.zip

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

• https://f5cfa4b-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/2619/head:pr_2619 && git checkout pr_2619
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.tag=1.24.0-f5cfa4b-amd64