Update the kind make targets to work with kind 0.6.0 and later.

[roberthbailey]

As described in the breaking changes section for the 0.6.0 release of kind:

You do not need to and should not do export KUBECONFIG="$(kind get kubeconfig-path)". This command is deprecated and will be removed in a future release.

I recently re-installed kind following the current installation instructions and got version 0.7.0 which indeed does remove this command (and our existing make targets were thus rendered broken).

[agones-bot]

Build Succeeded 👏

Build Id: a1da7446-6f03-46fc-ab63-c2e8347998a8

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

• image: gcr.io/agones-images/agones-controller:1.4.0-677838b
• image: gcr.io/agones-images/agones-sdk:1.4.0-677838b
• image: gcr.io/agones-images/agones-ping:1.4.0-677838b
• Linux C++ SDK (build): agonessdk-1.4.0-677838b-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.4.0-677838b.zip

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

• https://677838b-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/GoogleCloudPlatform/agones.git pull/1349/head:pr_1349 && git checkout pr_1349
• helm install ./install/helm/agones --namespace agones-system --name agones --set agones.image.tag=1.4.0-677838b

[roberthbailey]

/assign @markmandel

[roberthbailey]

[testing our prow webhook, which had been failing]

[markmandel]

I believe you when you say this works 😄

[google-oss-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• OWNERS [markmandel,roberthbailey]

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