Release 1.15.0-rc

[sawagh]

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

/kind release

What this PR does / Why we need it:

This includes all of the changes for the 1.15.0 release candidate.

Which issue(s) this PR fixes:

N/A

[agones-bot]

Build Succeeded 👏

Build Id: 7f84d6dd-4af7-4443-ba1c-0dd850d16943

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

• image: gcr.io/agones-images/agones-controller:1.15.0-43f85fb
• image: gcr.io/agones-images/agones-ping:1.15.0-43f85fb
• Linux C++ SDK (build): agonessdk-1.15.0-43f85fb-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.15.0-43f85fb.zip

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

• https://43f85fb-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/2121/head:pr_2121 && git checkout pr_2121
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.15.0-43f85fb

[steven-supersolid]

Ah I just realised when we edit package.json here we should instead be running npm version 1.15.0-rc (or equivalent) so it syncs package-lock.json. This does mean can't do the release with only a text editor though #2120

[google-oss-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: roberthbailey, sawagh, steven-supersolid

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• OWNERS [roberthbailey]

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