ci: missing tex installation

Author: m-muecke

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

@@ -46,6 +46,15 @@ jobs:
           extra-packages: any::rcmdcheck
           needs: check
 
+      - uses: r-lib/actions/setup-tinytex@v2
+        env:
+          TINYTEX_INSTALLER: TinyTeX
+
+      - name: Install additional LaTeX packages
+        run: |
+          tlmgr update --self
+          tlmgr install doublestroke relsize
+
       - uses: r-lib/actions/check-r-package@v2
         with:
           upload-snapshots: true