[ruby/sinatra-sequel] Enable WEB_CONCURRENCY=auto for puma (#10135)

frameworks/Ruby/sinatra-sequel/Gemfile

@@ -19,4 +19,5 @@ end
 
 group :puma, optional: true do
   gem 'puma', '~> 7.0', require: false
+  gem 'concurrent-ruby' # used by Puma for auto-tuning
 end

frameworks/Ruby/sinatra-sequel/Gemfile.lock

@@ -3,6 +3,7 @@ GEM
   specs:
     base64 (0.2.0)
     bigdecimal (3.1.9)
+    concurrent-ruby (1.3.5)
     iodine (0.7.58)
     json (2.13.2)
     logger (1.6.6)
@@ -42,6 +43,7 @@ PLATFORMS
   x86_64-linux
 
 DEPENDENCIES
+  concurrent-ruby
   iodine (~> 0.7)
   json (~> 2.8)
   pg (~> 1.5)

frameworks/Ruby/sinatra-sequel/sinatra-sequel-postgres.dockerfile

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

frameworks/Ruby/sinatra-sequel/sinatra-sequel.dockerfile

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