Adding further details on raw logs for integrations

[LucasC]

Partners can submit raw logs that are unrelated to their pipelines, making it hard to understand what their integrations is trying to perform. Adding more context in the doc to avoid this.

Merge instructions

• [x] Please merge after reviewing

[github-actions[bot]]

Preview links (active after the build_preview check completes)

Modified Files

• https://docs-staging.datadoghq.com/lucas.cerdan/apw-logs-raw-msg/developers/integrations/log_integration

[git-thuerk-done]

hi @LucasC I lost track of this one and it appears it has a merge conflict now, if you don't mind fixing the merge conflict then I'll get this merged for you, thanks ! :)