Pin semver to latest minor release

Author: JoshMock

.github/workflows/npm-publish-unstable.yml

@@ -72,7 +72,7 @@ jobs:
           # set unstable version value
           unstable_tag=$(echo "unstable.$(date --utc +%Y%m%d%H%M%S)")
           latest=$(npm view @elastic/elasticsearch --json | jq -r '.["dist-tags"].latest')
-          next=$(yes | npx semver -i minor "$latest")
+          next=$(npx -y 'semver@^7.7.0' -i minor "$latest")
           unstable_version=$(echo "$next-$unstable_tag")
 
           # overwrite package.json with unstable version value