Error when building logstash-filter-elasticsearch plugin

[jong99]

I'm trying to track down an issue I'm having with the logstash-filter-elasticsearch plugin so I've checked out the code and am trying to build from source.

Running inside a ruby:9.2 docker container I'm checking out the code then trying to build with

bundle install
bundle exec rspec
gem build *.gemspec

This is failing with the error

An error occurred while loading ./spec/filters/elasticsearch_spec.rb. - Did you mean?
                    rspec ./spec/filters/integration/elasticsearch_spec.rb

Failure/Error: require "elasticsearch/transport/transport/http/manticore"

LoadError:
  no such file to load -- elasticsearch/transport/transport/http/manticore
# /usr/local/bundle/gems/polyglot-0.3.5/lib/polyglot.rb:65:in `require'
# ./lib/logstash/filters/elasticsearch/client.rb:4:in `<main>'
# ./lib/logstash/filters/elasticsearch.rb:5:in `<main>'
# /usr/local/bundle/gems/polyglot-0.3.5/lib/polyglot.rb:65:in `require'
# ./spec/filters/elasticsearch_spec.rb:4:in `<main>'
# ------------------
# --- Caused by: ---
# Polyglot::PolyglotLoadError:
#   Failed to load elasticsearch/transport/transport/http/manticore using extensions rb, treetop, tt
#   /usr/local/bundle/gems/polyglot-0.3.5/lib/polyglot.rb:55:in `load'

An error occurred while loading ./spec/filters/integration/elasticsearch_spec.rb. - Did you mean?
                    rspec ./spec/filters/elasticsearch_spec.rb

Failure/Error: require "elasticsearch/transport/transport/http/manticore"

LoadError:
  no such file to load -- elasticsearch/transport/transport/http/manticore
# /usr/local/bundle/gems/polyglot-0.3.5/lib/polyglot.rb:65:in `require'
# ./lib/logstash/filters/elasticsearch/client.rb:4:in `<main>'
# ./lib/logstash/filters/elasticsearch.rb:5:in `<main>'
# /usr/local/bundle/gems/polyglot-0.3.5/lib/polyglot.rb:65:in `require'
# ./spec/filters/integration/elasticsearch_spec.rb:4:in `<main>'
# ------------------
# --- Caused by: ---
# Polyglot::PolyglotLoadError:
#   Failed to load elasticsearch/transport/transport/http/manticore using extensions rb, treetop, tt
#   /usr/local/bundle/gems/polyglot-0.3.5/lib/polyglot.rb:55:in `load'
Run options: exclude {:redis=>true, :socket=>true, :performance=>true, :couchdb=>true, :elasticsearch=>true, :elasticsearch_secure=>true, :export_cypher=>true, :integration=>true, :windows=>true}

If I check out v.3.8.0 then I can build successfully with the above commands, but it fails for all versions > v3.8.0

Am I missing a step in trying to build the plugin?