Improve logger and ignore Rack connection errors

Fixed

• When an Appsignal::Logger uses .broadcast_to to broadcast messages to other loggers, broadcast those messages even if the log level of those messages is lower than the logger's threshold. This allows other loggers to set their own logging thresholds.

  When the logger is silenced, messages below the silencing threshold are not broadcasted to other loggers.

• When an Appsignal::Logger uses .broadcast_to to broadcast messages to other loggers, broadcast the original message received by the logger, without formatting it or converting it to a string.

• Call the Appsignal::Logger formatter with the original message object given, rather than converting it to a string before calling the formatter.

• When an error is passed to an Appsignal::Logger as the message, format it regardless of the logging level. Previously it would only be formatted when passed to #error.

• Ignore Errno::ECONNRESET errors in the Rack wrapper.

View the Ruby gem v4.5.17 changelog for more information.