Replace TravisCI with Github Actions

[MasterOdin]

PR replaces the TravisCI configuration (which has not run in over a year) with one for Github Actions. This retains essentially all the same pieces of what Travis was doing, though with tweaks to get things to work in the "GH actions" way (e.g. such as using coveralls workflow, vs the npm coveralls package). See https://github.com/MasterOdin/react-redux-loading-bar/actions/runs/7335355578/ for what this looks like, where it's hooked up to upload to https://coveralls.io/github/MasterOdin/react-redux-loading-bar.

One suggestion would be to drop the usage of test:coveralls where doing | coveralls eats the test input, but instead use test:coverage (with --reporter=lcov), and then use coverallsapp/github-action to upload the coverage report, as it gives you the full test output, as is the more "blessed" way to do this, and avoids having to know to setup the COVERALLS_REPO_TOKEN value.

[mironov]

@MasterOdin Hey, thank you for migrating the CI configuration! Your suggestion about refactoring coveralls integration also makes sense. Unfortunately, I don't have the capacity to do that, but I'd be happy to accept a pull request.