use Monolog's FormatterInterface format method original signature

[remitamine]

the original Monolog's FormatterInterface format method signature does not impose any return type while the ElasticCommonSchemaFormatter does impose a return type of string:

ecs-logging-php/src/Elastic/Monolog/Formatter/ElasticCommonSchemaFormatter.php

Line 83 in 978b848

public function format(LogRecord $record): string

this change removes this limitation so it's possible to override the format method and return a different type(ex: array).

the usecase i have here is that i want to combine the ElasticCommonSchemaFormatter with a monolog handler that uses the fluent logger to send logs to fluent-bit, fluent-bit's forward protocol accept only messages in msgpack format, so messages are packed using msgpack php extension, since the message are encoded in a format other then JSON, there is no need here to encode the ecs message to json(currently it's automatically done in the format method)

ecs-logging-php/src/Elastic/Monolog/Formatter/ElasticCommonSchemaFormatter.php

Line 132 in 978b848

return $this->toJson($outRecord) . "\n";

and then later decode it, instead i would need only the formatted array so it can be further packed into a msgpack to be sent to fluent-bit.

[cla-checker-service]

❌ Author of the following commits did not sign a Contributor Agreement:
4df4b6b

Please, read and sign the above mentioned agreement if you want to contribute to this project