Bump cache for [pkgdown]; add session info

Author: jennybc

.github/workflows/pkgdown.yaml

@@ -43,8 +43,8 @@ jobs:
           path: |
             ${{ env.R_LIBS_USER }}/*
             !${{ env.R_LIBS_USER }}/pak
-          key: ubuntu-18.04-${{ steps.install-r.outputs.installed-r-version }}-1-${{ hashFiles('.github/r-depends.rds') }}
-          restore-keys: ubuntu-18.04-${{ steps.install-r.outputs.installed-r-version }}-1-
+          key: ubuntu-18.04-${{ steps.install-r.outputs.installed-r-version }}-2-${{ hashFiles('.github/r-depends.rds') }}
+          restore-keys: ubuntu-18.04-${{ steps.install-r.outputs.installed-r-version }}-2-
 
       - name: Install system dependencies
         if: runner.os == 'Linux'
@@ -59,6 +59,13 @@ jobs:
           pak::pkg_install("pkgdown")
         shell: Rscript {0}
 
+      - name: Session info
+        run: |
+          options(width = 100)
+          pkgs <- installed.packages()[, "Package"]
+          sessioninfo::session_info(pkgs, include_base = TRUE)
+        shell: Rscript {0}
+
       - name: Install package
         run: R CMD INSTALL .