Make log-level configurable in staging

The new comment and code come from the Rails 8.0 default files.

config/environments/production.rb

@@ -68,9 +68,7 @@ Rails.application.configure do
   # Prepend all log lines with the following tags.
   config.log_tags = [:request_id]
 
-  # "info" includes generic and useful information about system operation, but avoids logging too much
-  # information to avoid inadvertent exposure of personally identifiable information (PII). If you
-  # want to log everything, set the level to "debug".
+  # Change to "debug" to log everything (including potentially personally-identifiable information!)
   config.log_level = ENV.fetch("RAILS_LOG_LEVEL", "info")
 
   # Use a different cache store in production.

config/environments/staging.rb

@@ -35,8 +35,8 @@ Openfoodnetwork::Application.configure do
   # Use https in email links
   config.action_mailer.default_url_options = { protocol: 'https' }
 
-  # Set log level (default is :debug in Rails 4)
-  config.log_level = :info
+  # Change to "debug" to log everything (including potentially personally-identifiable information!)
+  config.log_level = ENV.fetch("RAILS_LOG_LEVEL", "info")
 
   # Configure logging:
   config.log_formatter = Logger::Formatter.new.tap { |f| f.datetime_format = "%Y-%m-%d %H:%M:%S" }