Bump Roxygen to v8.1.0

Change-Id: I9a1f2d53176dba7e28e8d5db1fbfa05d6551d1f3
diff --git a/DESCRIPTION b/DESCRIPTION
index 228cdc5..76c8909 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -32,4 +32,4 @@
 Config/testthat/edition: 3
 Encoding: UTF-8
 Roxygen: list(markdown = TRUE)
-RoxygenNote: 7.2.3
+Config/roxygen2/version: 8.1.0