Fix a couple of broken links on the website.

[roberthbailey]

What type of PR is this?

Uncomment only one /kind <> line, hit 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

I found this looking at the pages linked from #1703.

/assign @aLekSer

[pooneh-m]

Thanks for fixing the links.

[google-oss-robot]

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This pull-request has been approved by: pooneh-m, roberthbailey

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[agones-bot]

Build Succeeded 👏

Build Id: bd09f6db-1b71-4cfc-be71-24447967a7be

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

• image: gcr.io/agones-images/agones-controller:1.8.0-976f3b2
• image: gcr.io/agones-images/agones-sdk:1.8.0-976f3b2
• image: gcr.io/agones-images/agones-ping:1.8.0-976f3b2
• Linux C++ SDK (build): agonessdk-1.8.0-976f3b2-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.8.0-976f3b2.zip

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

• https://976f3b2-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/1704/head:pr_1704 && git checkout pr_1704
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.8.0-976f3b2