ci: fix changelog format

Author: Greewil

.github/workflows/release-notes-generation.yml

@@ -41,7 +41,9 @@ jobs:
           ./gen_release_notes.sh -i .. -lt -f changelog.md
           [ -f "changelog.md" ] && CHANGELOG=$(cat changelog.md) || CHANGELOG=''
           echo "$CHANGELOG"
-          echo "FINAL_CHANGELOG='$CHANGELOG'" >> "$GITHUB_OUTPUT"
+          echo 'FINAL_CHANGELOG<<EOF' >> $GITHUB_OUTPUT
+          echo "$CHANGELOG" >> $GITHUB_OUTPUT
+          echo 'EOF' >> $GITHUB_OUTPUT
 
           [ -f 'changelog.md' ] && echo "IS_EMPTY=false" >> "$GITHUB_OUTPUT"
           [ -f 'changelog.md' ] || echo "IS_EMPTY=true" >> "$GITHUB_OUTPUT"