Log Message:
(devel/R-covr) Updated 3.6.2 to 3.6.4

# covr 3.6.4

* Fix for a failing test on CRAN

# covr 3.6.3

* Updates to internal usage of `is.atomic()` to work with upcoming
  R release (@mmaechler , #542)

* `package_coverage()` now works correctly with ignore files when
   it is not run in the package root directory (@mpadge, #538)