Added a couple of tests to gameserverallocationpolicy

[akremsa]

What type of PR is this?

/kind cleanup

What this PR does / Why we need it:
Added a couple of new cases to unit tests

[agones-bot]

Build Succeeded 👏

Build Id: d674cdb7-481f-4239-a1e8-f3e7893db264

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

• image: gcr.io/agones-images/agones-controller:1.6.0-9b80383
• image: gcr.io/agones-images/agones-sdk:1.6.0-9b80383
• image: gcr.io/agones-images/agones-ping:1.6.0-9b80383
• Linux C++ SDK (build): agonessdk-1.6.0-9b80383-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.6.0-9b80383.zip

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

• https://9b80383-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/GoogleCloudPlatform/agones.git pull/1503/head:pr_1503 && git checkout pr_1503
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.6.0-9b80383

[pooneh-m]

Nice! Thanks for increasing test coverage.

[google-oss-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• OWNERS [pooneh-m]

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