Won't run on some old R versions because of {htmlTable}, testing macO…

…S arm64 image

.github/workflows/R-CMD-check.yaml

@@ -22,20 +22,15 @@ jobs:
       fail-fast: false
       matrix:
         config:
+          - {os: macos-13-xlarge,   r: 'release'}
           - {os: macos-latest,   r: 'release'}
-
           - {os: windows-latest, r: 'release'}
-          # Use 3.6 to trigger usage of RTools35
-          - {os: windows-latest, r: '3.6'}
           # use 4.1 to check with rtools40's older compiler
           - {os: windows-latest, r: '4.1'}
-
           - {os: ubuntu-latest,   r: 'devel', http-user-agent: 'release'}
           - {os: ubuntu-latest,   r: 'release'}
           - {os: ubuntu-latest,   r: 'oldrel-1'}
           - {os: ubuntu-latest,   r: 'oldrel-2'}
-          - {os: ubuntu-latest,   r: 'oldrel-3'}
-          - {os: ubuntu-latest,   r: 'oldrel-4'}
 
     env:
       GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}