Sherpa 4.13.0 This release of Sherpa coincides with the CIAO 4.13 release. The release contains a few minor documentation updates, a version number update to coincide with CIAO version 4.13.0, and infrastructure changes to migrate from Travis-CI to GitHub Actions for testing. No additional functionality has been introduced. Details 1043 - RTD: install more packages via pip Install sphinx-astropy and ipykernel via pip instead of Conda for the Read the Docs builds to avoid current indirect requirement conflicts. 1035 - Travis to GitHub Actions Replaces the Travis test infrastructure with two GitHub Actions workflows. 1036 - Cleaned up several typos in the RELEASE_NOTES file Updates the RELEASE_NOTES file to correct several typos. 1038 - Docs: note Python version and new build status Updates the build status badge to track GitHub Actions rather than Travis-CI and report the python versions as 3.6, 3.7, and 3.8.