Test compatibility with actions

[Khartir]

Description

As mentioned in #214 (comment) this moves the compatibilty tests to Github actions.
There currently seems to be an issue with cashing: Install still runs, although there is a cash hit. This is also the case on the existing action to test the examples.

Breaking changes

Removed test:compat and related scripts from package.json

Checklist

• Added / updated the unit tests
• Added / updated the documentation

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit fd12594:

Sandbox	Source
focused-fast-f3i8b	Configuration

[Khartir]

I'm unsure which tests should be run in which tool. Both Travis CI and and Circle CI ran lint and test:compat and reported the coverage.
For now I have changed them to only run yarn test, but I think it would be better to reduce the amount of tools.
I think we can drop Travis CI completely, since it doesn't do anything, that isn't also done by Circle CI or GitHub actions.

[codecov]

Codecov Report

Merging #230 into next will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             next     #230   +/-   ##
=======================================
  Coverage   98.58%   98.58%           
=======================================
  Files           8        8           
  Lines         424      424           
  Branches      148      140    -8     
=======================================
  Hits          418      418           
  Misses          6        6

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 39a9759...fd12594. Read the comment docs.

[ghengeveld]

@Khartir I'd like to have both CircleCI and Travis run the same tests. They have slightly different environments and that has proven to sometimes lead to false negatives but also false positives. In either case there's a problem that wouldn't have surfaced if we only used one. I don't want to spend too much time maintaining them both but if it's not extra work, I'm fine with keeping them both in place. We may eventually migrate to GitHub Actions altogether, but I'm not in a hurry to change anything in our current CI setup if there's no pressing need.