[ruby/sinatra] Let Puma decide the number of workers (#10120)

frameworks/Ruby/sinatra-sequel/config/mri_puma.rb

@@ -1,10 +1,9 @@
 require_relative 'auto_tune'
 
 # FWBM only... use the puma_auto_tune gem in production!
-num_workers, num_threads = auto_tune
+_, num_threads = auto_tune
 
-workers num_workers
-threads num_threads, num_threads
+threads num_threads
 
 before_fork do
   Sequel::DATABASES.each(&:disconnect)

frameworks/Ruby/sinatra/sinatra-postgres.dockerfile

@@ -13,6 +13,7 @@ WORKDIR /sinatra
 ENV BUNDLE_WITH=postgresql:puma
 RUN bundle install --jobs=4 --gemfile=/sinatra/Gemfile
 
+ENV WEB_CONCURRENCY=auto
 ENV DBTYPE=postgresql
 
 EXPOSE 8080

frameworks/Ruby/sinatra/sinatra.dockerfile

@@ -15,6 +15,7 @@ RUN bundle install --jobs=4 --gemfile=/sinatra/Gemfile
 
 ENV DBTYPE=mysql
 
+ENV WEB_CONCURRENCY=auto
 EXPOSE 8080
 
 CMD bundle exec puma -C config/mri_puma.rb -b tcp://0.0.0.0:8080 -e production