ci: auto-update checksum during release

Author: rcarcasses

.github/workflows/release.yml

@@ -20,6 +20,25 @@ jobs:
       - name: Checkout repository
         if: steps.release.outputs.release_created == 'true'
         uses: actions/checkout@v4
+      - name: Update README checksum
+        if: steps.release.outputs.release_created == 'true'
+        env:
+          TAG_NAME: ${{ steps.release.outputs.tag_name }}
+        run: |
+          set -euo pipefail
+          curl -Ls "https://github.com/${GITHUB_REPOSITORY}/archive/refs/tags/${TAG_NAME}.tar.gz" -o source.tar.gz
+          SHA=$(shasum -a 256 source.tar.gz | awk '{print $1}')
+          rm source.tar.gz
+          sed -i "s/sha256 = \"[0-9a-f]\{64\}\"/sha256 = \"${SHA}\"/" README.md
+          if git diff --quiet README.md; then
+            echo "Checksum already up to date"
+          else
+            git config user.name "github-actions[bot]"
+            git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+            git add README.md
+            git commit -m "docs: update checksum for ${TAG_NAME}"
+            git push
+          fi
       - name: Enrich release notes with install instructions
         if: steps.release.outputs.release_created == 'true'
         env: