Logstash errors with writing plugins

Elastic Stack Logstash
1

I am creating a logstash plugins while running bundle exec rspec command

     Failure/Error:
       raise LogStash::ConfigurationError,
         I18n.t("logstash.runner.configuration.invalid_plugin_settings")

     LogStash::ConfigurationError:
       Something is wrong with your configuration.
     Shared Example Group: "an interruptible input plugin" called from ./spec/inputs/grpc_spec.rb:8
     # /usr/local/rvm/gems/jruby-9.2.9.0/gems/logstash-core-5.6.4-java/lib/logstash/config/mixin.rb:114:in `config_init'
     # /usr/local/rvm/gems/jruby-9.2.9.0/gems/logstash-core-5.6.4-java/lib/logstash/inputs/base.rb:62:in `initialize'
     # /usr/local/rvm/gems/jruby-9.2.9.0/gems/logstash-devutils-1.3.6-java/lib/logstash/devutils/rspec/shared_grpc.rb:6:in `block in subject'
     # /usr/local/rvm/gems/jruby-9.2.9.0/gems/logstash-devutils-1.3.6-java/lib/logstash/devutils/rspec/shared_grpc.rb:7:in `block in <main>'
     # /usr/local/rvm/gems/jruby-9.2.9.0/gems/rspec-wait-0.0.10/lib/rspec/wait.rb:47:in `block in <main>'

Finished in 0.14091 seconds (files took 7.26 seconds to load)
1 example, 1 failure

Failed examples:

rspec ./spec/inputs/grpc_spec.rb:8 # LogStash::Inputs::Grpc behaves like an interruptible input plugin #stop returns from run