ci: update setup-r to v2 and use the R version specified in renv.lock

Author: asiripanich

.github/workflows/snap-gtfs.yaml

@@ -19,8 +19,9 @@ jobs:
         with: 
           fetch-depth: '0'
 
-      - uses: r-lib/actions/setup-r@v1
+      - uses: r-lib/actions/setup-r@v2
         with:
+          r-version: '4.2.1'
           use-public-rspm: true
 
       - uses: r-lib/actions/setup-pandoc@v1