Tag to be used with the master branch of atlas/athena. Update(s) since 2.0.75: - Updated all "standalone externals" to the versions provided by LCG_98python3; - Removed the FFTW package from the repository, setting up AthenaExternals to rather pick it up from LCG; - Updated how Acts would find Boost and Eigen from the LCG release; - Updated how GeoModelTools would pick up nlohmann_json from the LCG release.