[R2] Add Github Actions badges

[wl2484]

* Tasks:
    * Add a CI Build status badge to README.md
    * Add a CodeCov test coverage badge to README.md
* Acceptance Criteria:
    * In README.md on the master branch, there’s (1) a CI Build status badge showing “passing”, and (2) a CodeCov test coverage badge showing 97% test coverage

As a developer, I need to add a CI Build status badge and a CodeCov test coverage badge to the README.md file, So that users can easily see the build status and test coverage of the project.

Details and Assumptions

• The project is hosted on a version control system that supports CI builds and CodeCov integration.
• The README.md file is present in the root directory of the project.
• The CI build status badge will display the current build status of the project.

• The CodeCov test coverage badge will show the test coverage percentage, which should be higher than 97% in this case.

  Acceptance Criteria

  Given that I am on the master branch,
  When I open the README.md file,
  Then I should see a CI Build status badge indicating that the build is passing,
  And I should also see a CodeCov test coverage badge showing a 97% or higher test coverage.

[momo100110]

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