Add port flag to example allocator-client

[robbieheywood]

What type of PR is this?
/kind feature

What this PR does / Why we need it:
It adds the ability to specify --port <port> when using the allocator-client in examples/allocator-client. Without this, you can only use this allocator-client to hit allocators exposed on port 443. We expose our allocator through istio on a non-443 port, so this change is required to use the client to test our allocator.

Which issue(s) this PR fixes:

n/a - haven't raised a corresponding issue (but I'm happy to if required).

Special notes for your reviewer:
I've tested this by running go run examples/allocator-client/main.go --ip <allocator-ip> --namespace game-scavengers --key tls.key --cert tls.crt --cacert ca.crt --port <port> against a v1.6 allocator running in GKE, exposed on a non-443 port, and it succeeded. Let me know if you feel this needs any more testing.

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[robbieheywood]

@googlebot I signed it!

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[pooneh-m]

Thanks for the change @robbieheywood. Please also include the flag in the example here: https://github.com/googleforgames/agones/blob/master/site/content/en/docs/Advanced/allocator-service.md

[google-oss-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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[agones-bot]

Build Succeeded 👏

Build Id: fa6a0cf3-acbf-44bc-b927-59f34f975ef9

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

• image: gcr.io/agones-images/agones-controller:1.7.0-9bea142
• image: gcr.io/agones-images/agones-sdk:1.7.0-9bea142
• image: gcr.io/agones-images/agones-ping:1.7.0-9bea142
• Linux C++ SDK (build): agonessdk-1.7.0-9bea142-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.7.0-9bea142.zip

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

• https://9bea142-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/GoogleCloudPlatform/agones.git pull/1618/head:pr_1618 && git checkout pr_1618
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.7.0-9bea142

[google-oss-robot]

New changes are detected. LGTM label has been removed.

[robbieheywood]

Thanks for the review @pooneh-m - hopefully this is now good to go 👍

[agones-bot]

Build Failed 😱

Build Id: 3cbc1278-63a7-422c-85b4-89659f1fabac

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• Cloud Build log download

To get permission to view the Cloud Build view, join the agones-discuss Google Group.

[agones-bot]

Build Failed 😱

Build Id: f9d64c54-ea6c-42ff-b55a-f498b04fb544

• Cloud Build view
• Cloud Build log download

To get permission to view the Cloud Build view, join the agones-discuss Google Group.

[markmandel]

That's a new flaky one I haven't seen before:

time="2020-06-07 22:29:37.009" level=info msg="sent UDP packet" address="34.82.230.193:7320" test=TestGameServerUnhealthyAfterReadyCrash
time="2020-06-07 22:29:37.225" level=info msg="Waiting for states to match" awaitingState=Ready currentState=Unhealthy gs=udp-servernpl27
time="2020-06-07 22:29:38.221" level=info msg="Waiting for states to match" awaitingState=Ready currentState=Unhealthy gs=udp-servernpl27
time="2020-06-07 22:29:39.222" level=info msg="Waiting for states to match" awaitingState=Ready currentState=Unhealthy gs=udp-servernpl27
time="2020-06-07 22:29:40.222" level=info msg="Waiting for states to match" awaitingState=Ready currentState=Unhealthy gs=udp-servernpl2

Never gets to Ready and times out.

[agones-bot]

Build Succeeded 👏

Build Id: 830c5324-d0fa-49bb-bba6-55441f97eb40

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

• image: gcr.io/agones-images/agones-controller:1.7.0-c7897f2
• image: gcr.io/agones-images/agones-sdk:1.7.0-c7897f2
• image: gcr.io/agones-images/agones-ping:1.7.0-c7897f2
• Linux C++ SDK (build): agonessdk-1.7.0-c7897f2-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.7.0-c7897f2.zip

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

• https://c7897f2-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/GoogleCloudPlatform/agones.git pull/1618/head:pr_1618 && git checkout pr_1618
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.7.0-c7897f2

[pooneh-m]

Thanks @robbieheywood!