Refactored sdk functions to always return &alpha.Bool{} instead of nil

[justjoeyuk]

What type of PR is this?

/kind bug

What this PR does / Why we need it:
This PR fixes the issue presented in #1957 wherein the SDK returns a nil value for an ok value instead of an alpha.Bool{ Bool: false }. This PR ensures that the SDK always returns a value for ok and that users can expect an ok value to always be non-nil.

Which issue(s) this PR fixes:
Work on #1957

Special notes for your reviewer:
This is my first contribution - so I may have made a few errors of judgement in places. I'm happy to hear feedback and make the relevant changes.

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[agones-bot]

Build Failed 😱

Build Id: 1f1b0dbd-2b59-481b-a833-12a2d508e521

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[agones-bot]

Build Succeeded 👏

Build Id: 1750ee46-67f9-4c88-b1ec-93a5b9c42947

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

• image: gcr.io/agones-images/agones-controller:1.12.0-eec8942
• image: gcr.io/agones-images/agones-sdk:1.12.0-eec8942
• image: gcr.io/agones-images/agones-ping:1.12.0-eec8942
• Linux C++ SDK (build): agonessdk-1.12.0-eec8942-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.12.0-eec8942.zip

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

• https://eec8942-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/1958/head:pr_1958 && git checkout pr_1958
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.12.0-eec8942

[markmandel]

Thanks for this!

Can we switch Closes #1957 to Work on #1957?

This is a great first start, but we'll likely also want at least an e2e test to confirm that this actually closes the bug in question, so we won't want to close the issue until that is done.

Unless you want to add an e2e test to this PR, or we can have it happen in a separate PR, either way is totally fine 👍

[markmandel]

Can we switch Closes #1957 to Work on #1957?

If you are happy with it, I can make this change via GitHub (forgot I can do this) - if we want to push this through before RC next week.

But wanted to ask permission first before messing with your PR.

Let me know!

[markmandel]

LGTM!

[google-oss-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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[google-oss-robot]

New changes are detected. LGTM label has been removed.

[agones-bot]

Build Succeeded 👏

Build Id: 128a09cf-07ff-4d3e-8853-dd7385d2b2ea

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

• image: gcr.io/agones-images/agones-controller:1.12.0-443e54e
• image: gcr.io/agones-images/agones-sdk:1.12.0-443e54e
• image: gcr.io/agones-images/agones-ping:1.12.0-443e54e
• Linux C++ SDK (build): agonessdk-1.12.0-443e54e-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.12.0-443e54e.zip

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

• https://443e54e-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/1958/head:pr_1958 && git checkout pr_1958
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.12.0-443e54e