Bump the required Ruby version to 3.1.0

Until now, Rails only droped compatibility with older
rubies on new majors, but I propose to change this policy
because it causes us to either keep compatibility with long
EOLed rubies or to bump the Rails major more often, and to
drop multiple Ruby versions at once when we bump the major.

In my opinion it's a bad alignments of incentives. And we'd
be much better to just drop support in new minors whenever they
go EOL (so 3 years).

Also Ruby being an upstream dependency, it's not even
a semver violation AFAICT.

Since Rails 7.2 isn't planned before a few months, we
can already drop Ruby 3.0 as it will be EOL in March.

actioncable/actioncable.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "WebSocket framework for Rails."
   s.description = "Structure many real-time application concerns into channels over a single WebSocket connection."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

actionmailbox/actionmailbox.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Inbound email handling framework."
   s.description = "Receive and process incoming emails in Rails applications."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license  = "MIT"
 

actionmailer/actionmailer.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Email composition and delivery framework (part of Rails)."
   s.description = "Email on Rails. Compose, deliver, and test emails using the familiar controller/view pattern. First-class support for multipart email and attachments."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

actionpack/actionpack.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Web-flow and rendering framework putting the VC in MVC (part of Rails)."
   s.description = "Web apps on Rails. Simple, battle-tested conventions for building and testing MVC web applications. Works with any Rack-compatible server."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

actiontext/actiontext.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Rich text framework."
   s.description = "Edit and display rich text in Rails applications."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license  = "MIT"
 

actionview/actionview.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Rendering framework putting the V in MVC (part of Rails)."
   s.description = "Simple, battle-tested conventions and helpers for building web pages."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

activejob/activejob.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Job framework with pluggable queues."
   s.description = "Declare job classes that can be run by a variety of queuing backends."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

activemodel/activemodel.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "A toolkit for building modeling frameworks (part of Rails)."
   s.description = "A toolkit for building modeling frameworks like Active Record. Rich support for attributes, callbacks, validations, serialization, internationalization, and testing."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

activerecord/activerecord.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Object-relational mapper framework (part of Rails)."
   s.description = "Databases on Rails. Build a persistent domain model by mapping database tables to Ruby classes. Strong conventions for associations, validations, aggregations, migrations, and testing come baked-in."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

activestorage/activestorage.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Local and cloud file storage framework."
   s.description = "Attach cloud and local files in Rails applications."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

activesupport/activesupport.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "A toolkit of support libraries and Ruby core extensions extracted from the Rails framework."
   s.description = "A toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Rich support for multibyte strings, internationalization, time zones, and testing."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

rails.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Full-stack web application framework."
   s.description = "Ruby on Rails is a full-stack web framework optimized for programmer happiness and sustainable productivity. It encourages beautiful code by favoring convention over configuration."
 
-  s.required_ruby_version     = ">= 2.7.0"
+  s.required_ruby_version     = ">= 3.1.0"
   s.required_rubygems_version = ">= 1.8.11"
 
   s.license = "MIT"

railties/railties.gemspec

@@ -9,7 +9,7 @@
   s.summary     = "Tools for creating, working with, and running Rails applications."
   s.description = "Rails internals: application bootup, plugins, generators, and rake tasks."
 
-  s.required_ruby_version = ">= 2.7.0"
+  s.required_ruby_version = ">= 3.1.0"
 
   s.license = "MIT"
 

tools/rail_inspector/rail_inspector.gemspec

@@ -11,7 +11,7 @@
   spec.summary = "A collection of linters for rails/rails"
   spec.homepage = "https://github.com/skipkayhil/rail_inspector"
   spec.license = "MIT"
-  spec.required_ruby_version = ">= 2.7.0"
+  spec.required_ruby_version = ">= 3.1.0"
 
   spec.metadata["homepage_uri"] = spec.homepage
   spec.metadata["source_code_uri"] = spec.homepage