Tag to be used with the master branch of atlas/athena. Update(s) since 2.0.106: - Updated AnalysisBaseExternals to use external versions in sync with LCG_100; * Introduced simple patches for KLFitter and BAT to make them compatible with ROOT 6.24/00; * Upgraded Boost to version 1.75.0; * Upgraded HDF5 to version 1.10.6; * Upgraded libxml2 to version 2.9.10; * Upgraded nlohmann_json to version 3.9.1; * Upgraded Cython to version 0.29.21 and pip to version 21.0.1 (both as part of the PyAnalysis package); * Upgraded XRootD to version 5.1.1; * Building OpenSSL 1.1.1 for XRootD, if it is not available on the build system already; * Upgraded ROOT to version 6.24/00. - Introduced the PRIVATE_WORKING_DIRECTORY option for atlas_add_test(...); - Made FindGaudi.cmake compatible with the latest Gaudi master version.