Set a default statement timeout for postgres to 5s

[justiniso]

What does this PR do?

This PR updates the Postgres integration to set a default timeout of 5s on queries. Based on internal benchmarking, this should be a wide margin to ensure we mitigate performance impact in the worst case scenarios, while still ensuring customers have metrics.

Motivation

Datadog strives to provide high fidelity telemetry while guaranteeing the lowest possible performance impact by the agent. While the integrations do not run any queries that should exceed a 5s execution time, there are certain failure scenarios on databases that could result in all queries being slow and consuming more resources than a monitoring tool should–especially on a loaded database.

Additional Notes

I believe the biggest risk in changing this behavior is the impact on long-running custom queries. However the benefit to risk ratio is very hight.

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• PR title must be written as a CHANGELOG entry (see why)
• Files changes must correspond to the primary purpose of the PR as described in the title (small unrelated changes should have their own PR)
• PR must have changelog/ and integration/ labels attached

[codecov]

Codecov Report

Merging #9847 (0fd772e) into master (a0ede59) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Flag	Coverage Δ
postgres	92.16% <100.00%> (+0.24%)	⬆️

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[ruthnaebeck]

👍 for docs