Fix the default value for helm.installTests in the documentation.

[roberthbailey]

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:

Which issue(s) this PR fixes:

Closes #2720

Special notes for your reviewer:
@john-haven

[agones-bot]

Build Succeeded 👏

Build Id: fb8091fd-53b3-408f-9f6e-657992005478

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:1.26.0-4cd4f3b-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.26.0-4cd4f3b-linux-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.26.0-4cd4f3b-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.26.0-4cd4f3b-amd64
• Linux C++ SDK (build): agonessdk-1.26.0-4cd4f3b-amd64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.26.0-4cd4f3b-amd64.zip

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

• https://4cd4f3b-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/2722/head:pr_2722 && git checkout pr_2722
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.tag=1.26.0-4cd4f3b-amd64

[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.

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• OWNERS [markmandel,roberthbailey]

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[google-oss-prow]

New changes are detected. LGTM label has been removed.

[agones-bot]

Build Succeeded 👏

Build Id: 4337c3c2-ced8-4113-9319-bb364290e1d9

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:1.26.0-3852947-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.26.0-3852947-linux-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.26.0-3852947-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.26.0-3852947-amd64
• Linux C++ SDK (build): agonessdk-1.26.0-3852947-amd64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.26.0-3852947-amd64.zip

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

• https://3852947-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/2722/head:pr_2722 && git checkout pr_2722
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.tag=1.26.0-3852947-amd64