chore: Upgrade to Ruby 3.2.1 & Rails 6.0

* chore: upgrade to rails 6.0

* chore: upgrade ruby to 3.2.1

* chore: upgrade bundler

* chore: upgrade execjs

* chore: upgrade to rails 6.1

* chore: switch to sentry-ruby from raven

* chore: add extra platforms to gemfile

config/initializers/sentry.rb

@@ -1,14 +1,7 @@
 require "postal/config"
 
 if Postal.config.general&.exception_url
-  require "raven"
-  Raven.configure do |config|
+  Sentry.init do |config|
     config.dsn = Postal.config.general.exception_url
-    config.environments = ["production"]
-    if ENV["DEV_EXCEPTIONS"]
-      config.environments << "development"
-    end
-    config.silence_ready = true
-    config.tags = { process: ENV.fetch("PROC_NAME", nil) }
   end
 end