Add Ubuntu support for R version 4.4.1

Signed-off-by: Aksel Thomsen <thomsenaksel@gmail.com>

Author: akselthomsen

.github/workflows/check_nn_versions.yaml

@@ -51,7 +51,8 @@ jobs:
           - os: macos-latest
             date: 2023-10-25
             r: 4.3.1
-          - date: 2024-08-06
+          - os: ubuntu-latest
+            date: 2024-08-06
             r: 4.4.1
     env:
       R_KEEP_PKG_SOURCE: 'yes'