gh-39288: Fix the new release workflow by escaping special characters
    
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The new release creation workflow introduced by
#39194 failed for the latest
release:

https://github.com/sagemath/sage/actions/runs/12612595224/job/3514974517
9

with the message "Problems parsing JSON". See the "Create release" step.
Reported by passagemath/passagemath#638

We fix it by escaping special characters in `release_notes` for json
input.

test: https://github.com/kwankyu/sage/releases/tag/10.7.beta3
test workflow run:
https://github.com/kwankyu/sage/actions/runs/12620257460/job/35165981375

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URL: #39288
Reported by: Kwankyu Lee
Reviewer(s): Soham Rane

Author: Release Manager

.github/workflows/dist.yml

@@ -135,6 +135,8 @@ jobs:
               \"tag_name\": \"${{ github.ref_name }}\",
               \"previous_tag_name\": \"$latest_release_tag\"
             }" | jq -r '.body')
+          # escape special characters for json
+          release_notes=$(jq -R -s '.' <<< "$release_notes")
           curl -L \
             -X POST \
             -H "Accept: application/vnd.github+json" \
@@ -144,7 +146,7 @@ jobs:
             -d "{
               \"tag_name\": \"${{ github.ref_name }}\",
               \"prerelease\": ${{ contains(github.ref, 'beta') || contains(github.ref, 'rc') }},
-              \"body\": \"$release_notes\"
+              \"body\": $release_notes
             }"
       - name: Create release assets
         uses: softprops/action-gh-release@v2