Add ability to override error handling of R CMD check

Author: alecw

.github/workflows/R-reusable.yml

@@ -9,7 +9,7 @@ on:
       error-on:
         required: false
         type: string
-        default: "warning"
+        default: 'warning'
 
 
 name: Build and check an R package
@@ -69,4 +69,4 @@ jobs:
           working-directory: R/bican.mccarroll.${{ inputs.package_name }}
           upload-snapshots: true
           build_args: 'c("--no-manual","--compact-vignettes=gs+qpdf")'
-          error-on: ${{ inputs.error-on }}
+          error-on: '"'${{ inputs.error-on }}'"'