feat: add workflow to rebuild README.Rmd automatically

- when CI rebuilds README.Rmd it should also use the badge of the git-branch so the codecov gets an update

.github/workflows/render-rmarkdown.yaml

@@ -0,0 +1,38 @@
+# Workflow derived from https://github.com/r-lib/actions/tree/v2/examples
+# Need help debugging build failures? Start at https://github.com/r-lib/actions#where-to-find-help
+
+# Controls when the action will run: for now dev and master
+on:
+  push:
+    branches: [master, dev]
+
+name: render-rmarkdown
+
+jobs:
+  render-rmarkdown:
+    runs-on: ubuntu-latest
+    env:
+      GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
+    steps:
+    # Checks-out golem repo so the job can access it
+      - name: Checkout repo
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+      - uses: r-lib/actions/setup-pandoc@v2
+      - uses: r-lib/actions/setup-r@v2
+      - uses: r-lib/actions/setup-renv@v2
+
+    # install CRAN packages used inside README.Rmd
+      - name: install required packages
+        run: Rscript -e 'install.packages(c("rmarkdown", "covr"))'
+    # Render READEME.md using rmarkdown
+      - name: render README
+        run: Rscript -e 'rmarkdown::render("README.Rmd", output_format = "md_document")'
+      - name: Render Rmarkdown files and Commit Results
+        run: |
+          git config --local user.name "$GITHUB_ACTOR"
+          git config --local user.email "$GITHUB_ACTOR@users.noreply.github.com"
+          git add README.md
+          git commit -m "Re-build README.md" || echo "No changes to commit"
+          git push origin || echo "No changes to commit"