CI: GitHub Actions

[kmoe]

Remove the old Travis config, and run PR tests via GitHub Actions.

The krb5-user package is required for kinit, used in acceptance.sh.

We skip TestAccDataDnsTxtRecordSet_Basic due to a failure we can't reproduce anywhere except the GHA runner and will need to investigate later: #154

[bflad]

Ready for updates from other similar pull requests! 👍

[kmoe]

Could the fail be related to the CGO DNS issues (golang/go#25321 etc)?

[kmoe]

The test failure:

=== RUN   TestAccDataDnsTxtRecordSet_Basic
    data_dns_txt_record_set_test.go:13: Step 1/1 error: Error running pre-apply refresh: exit status 1
        2021/06/24 15:53:58 [DEBUG] Using modified User-Agent: Terraform/0.12.30 HashiCorp-terraform-exec/0.13.3
        
        Error: error looking up TXT records for "terraform.io": lookup terraform.io on 127.0.0.53:53: no such host
        
          on terraform_plugin_test.tf line 2, in data "dns_txt_record_set" "test":
           2: data "dns_txt_record_set" "test" {
        
        
--- FAIL: TestAccDataDnsTxtRecordSet_Basic (11.55s)

[bflad]

macOS support may require some parts of #144, but unsure how the runners differ from an actual workstation.

[bflad]

Looks great! Thank you for opening that separate issue and implementing the TXT data source test workaround for now. 🚀

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active contributions.
If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.