fix: fix bad substitution error (#345)

Author: astuyve

scripts/publish_prod.sh

@@ -86,7 +86,7 @@ echo "Publishing to https://pypi.org/project/datadog-lambda/"
 
 echo
 echo 'Publishing updates to github'
-git commit pyproject.toml -m "Bump version to ${$NEW_VERSION}"
+git commit pyproject.toml -m "Bump version to ${NEW_VERSION}"
 git push origin main
 git tag "v$LAYER_VERSION"
 git push origin "refs/tags/v$LAYER_VERSION"