Minor maintenance update Test environments local ubuntu install, R 4.1.2 ubuntu 18.04 (on Github Actions), R devel, 4.1.2, 4.0.5, 3.6.3, 3.5.3 windows (on Github Actions), R 4.1.2, 3.6.3 macOS (on Github Actions), R 4.1.2 R CMD check results 0 errors | 0 warnings | 0 notes