Add GitHub Action setting file

[y-yu]

• Travis CI( travis-ci.com ) has been required an application to use their resource unlimitedly even though we are OSS works
  • https://blog.travis-ci.com/2020-11-02-travis-ci-new-billing

  • We will be offering an allotment of OSS minutes that will be reviewed and allocated on a case by case basis. Should you want to apply for these credits please open a request with Travis CI support stating that you’d like to be considered for the OSS allotment

• We use travis-ci.org so it's not irrelevant for now.....
  • But travis-ci.org is now deprecated 😢
  • Since travis-ci.org is using GitHub V1 API, it causes many problems such like the build status would not be updated
    • For example: Is Travis CI testing NOT working? gfngfn/SATySFi#224
  • In the common sense, we have to move travis-ci.com even if we keep using Travis CI
• Then I make GitHub Action setting, which could be the next our CI service
  • Example result: https://github.com/y-yu/qulacs/actions/runs/362695201
    • It's done in 40 minutes
      
    • It seems to be tow times faster than the current Travis CI