Automatically test with the latest Kubernetes version

[nolar]

Replace the explicit Kubernetes versions in CI/CD with the "latest" aliases.

Issue : #13

Description

Previously, all Kubernetes versions were explicitly enumerated in the CI/CD config. We had to add new Kubernetes versions from time to time. Same for Minikube.

Now, the "latest" will be used for both. Extra versions versions to test still have to be listed explicitly (to my knowledge, there is no "latest minus 1", "latest minus 2", or so).

Now, the Travis build looks like this:

Types of Changes

• Refactor/improvements

[zincr]

🤖 zincr found 0 problems , 0 warnings

✅ Large Commits
✅ Approvals
✅ Specification
✅ Dependency Licensing

[zincr]

🤖 zincr found 1 problem , 0 warnings

❌ Approvals
✅ Large Commits
✅ Specification
✅ Dependency Licensing

Details on how to resolve are provided below

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Approvals

All proposed changes must be reviewed by project maintainers before they can be merged

Not enough people have approved this pull request - please ensure that 1 additional user, who have not contributed to this pull request approve the changes.

• ✅ Approved by PR author @nolar
• ❌ 1 additional approval needed
   

[jonathanbeber]

+1