Add dependency on "rackup"

Webrick support was removed from rack to this gem!

Author: errm

Gemfile.lock

@@ -6,6 +6,7 @@ PATH
       activesupport (> 6.0, < 8.0)
       prometheus-client-mmap (~> 1.1)
       rack
+      rackup
 
 GEM
   remote: https://rubygems.org/

exe/promenade

@@ -2,6 +2,7 @@
 
 require "promenade"
 require "rack"
+require "rackup"
 require "prometheus/client/rack/exporter"
 
 Promenade.setup
@@ -15,6 +16,6 @@ app = Rack::Builder.app do
   run ->(_env) { [404, {}, ["visit /metrics for metrics"]] }
 end
 
-Signal.trap("TERM") { Rack::Handler::WEBrick.shutdown }
+Signal.trap("TERM") { Rackup::Handler::WEBrick.shutdown }
 
-Rack::Handler::WEBrick.run app, Port: ENV.fetch("PORT", "9394"), Host: "0.0.0.0"
+Rackup::Handler::WEBrick.run app, Port: ENV.fetch("PORT", "9394"), Host: "0.0.0.0"

promenade.gemspec

@@ -28,6 +28,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency "activesupport", "> 6.0", "< 8.0"
   spec.add_dependency "prometheus-client-mmap", "~> 1.1"
   spec.add_dependency "rack"
+  spec.add_dependency "rackup"
   spec.add_development_dependency "bundler", "~> 2.0"
   spec.add_development_dependency "byebug"
   spec.add_development_dependency "climate_control"