GA: Don't test on R 3.2.x and 3.3.x because plyr is not available

Author: HenrikBengtsson

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

@@ -6,7 +6,7 @@ jobs:
   R-CMD-check:
     runs-on: ${{ matrix.config.os }}
     name: ${{ matrix.config.os }} (${{ matrix.config.r }})
-    if: "! contains(github.event.head_commit.message, '[ci skip]')"
+    if: "! contains(github.event.head_commit.message, '[ci skip]')"    
 
     strategy:
       fail-fast: false
@@ -18,8 +18,6 @@ jobs:
         - { os: macOS-latest, r: '3.5'}
         - { os: macOS-latest, r: '3.6'}
         - { os: macOS-latest, r: 'devel'}
-        - { os: ubuntu-16.04, r: '3.2', cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
-        - { os: ubuntu-16.04, r: '3.3', cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
         - { os: ubuntu-16.04, r: '3.4', cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
         - { os: ubuntu-16.04, r: '3.5', cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
         - { os: ubuntu-16.04, r: '3.6', cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}