Fix config.read_encrypted_secrets deprecation warning quoting

Commit 0c76f17 deprecated `Rails::Application::Configuration#read_encrypted_secrets`
but, suprisingly, deprecation used backticks instead of normal quoting.

Author: viralpraxis

railties/lib/rails/application/configuration.rb

@@ -350,14 +350,13 @@ def enable_reloading=(value)
       end
 
       def read_encrypted_secrets
-        Rails.deprecator.warn(`config.read_encrypted_secrets is deprecated and will be removed in Rails 7.3.`)
+        Rails.deprecator.warn("'config.read_encrypted_secrets' is deprecated and will be removed in Rails 7.3.")
       end
 
       def read_encrypted_secrets=(value)
-        Rails.deprecator.warn(`config.read_encrypted_secrets is deprecated and will be removed in Rails 7.3.`)
+        Rails.deprecator.warn("'config.read_encrypted_secrets=' is deprecated and will be removed in Rails 7.3.")
       end
 
-
       def encoding=(value)
         @encoding = value
         silence_warnings do