Fix kitchen test for terraform 0.12.x

[bigwheel]

PR o'clock

Description

Fix kitchen test for terraform 0.12.x.

Test codes are written 6 months ago and it was broken because it supported only terraform 0.11.x.
In 6 months, eks module's least support version bumped to 0.12.x therefore test codes didn't work completely.

This PR ups test library versions and fix broken point.

Checklist

• Change added to CHANGELOG.md. All changes must be added and breaking changes and highlighted
  • I think no need to do it
• CI tests are passing
  • Unfortunately, in this module CI test is not running. The test with real AWS resources need real money.
• README.md has been updated after any changes to variables and outputs. See https://github.com/terraform-aws-modules/terraform-aws-eks/#doc-generation
  • no need

[bigwheel]

P.S.

I think that gruntwork-io/terratest is best may be good for terraform module test.
But, firstly I fix existing test.

[max-rocket-internet]

I opened a PR to just remove the kitchen stuff #787

I don't think it's valuable. Would you agree?

[bigwheel]

@max-rocket-internet
Basically agree.
I believe terraform test is valuable but terraform-aws-eks couldn't use it well.
Let's remove.

[github-actions]

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