out_cloudwatch_logs: log_group_class option introduced breaking change in 3.0.7

[nicolas-laduguie]

Bug Report

Describe the bug
Release 3.0.7 delivered the new log_group_class option support for cloudwatch output, but this introduces a breaking change, causing fluentbit not able to start.

To Reproduce

• Run 3.0.6 version of fluentbit with cloudwatch output option auto_create_group set to Off => should work fine
• Keep same config and run fluentbit 3.0.7 => fail starting with following error :

[2024/06/12 00:07:27] [error] [output:cloudwatch_logs:cloudwatch_logs.0] Configuring log_group_class requires `auto_create_group On`.

Expected behavior
Since 3.0.7 is a patch revision, should not introduce any breaking change and should work well with a configuration compliant with 3.0.6.

Your Environment

• Version used: 3.0.7
• Configuration:

[OUTPUT]
    Name cloudwatch_logs
    Match *
    region us-west-2
    log_group_name XXX
    log_stream_prefix XXX
    auto_create_group Off

• Operating System and version: Ubuntu 22.04

[nicolas-laduguie]

The change introducing the breaking change : #8832

[michael-stevens]

I've also seen this issue.

[lecaros]

ping @PettitWesley @edsiper