Feat/gitlab runner concurrency

[Falltrades]

Issues liées

Closes: #921

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Quel est le comportement actuel ?

WARNING: CONFIGURATION: Long polling issues detected.
Issues found:
  - Request bottleneck: 1 runners have request_concurrency=1, causing job delays during long polling
This can cause job delays matching your GitLab instance's long polling timeout.
Recommended solutions:
  1. Increase 'request_concurrency' to 2-4 for 1 runners currently using request_concurrency=1
Note: The 'FF_USE_ADAPTIVE_REQUEST_CONCURRENCY' feature flag can help automatically adjust request_concurrency based on workload.
This message will be printed each time the configuration is reloaded if the issues persist.
See documentation: https://docs.gitlab.com/runner/configuration/advanced-configuration.html#long-polling-issues  builds=0 max_builds=10

Quel est le nouveau comportement ?

Follow warning configuration.

Cette PR introduit-elle un breaking change ?

No.

Autres informations

Working fine on a development cluster.