incident-28477: update CentOS AMI

[agent-platform-auto-pr]

This PR bumps the test-infra-definitions submodule to 992f221157aa5ed7e878b33b92832da1dd8737f5 from f0aa9d321bac.
Here is the full changelog between the two commits: DataDog/test-infra-definitions@f0aa9d3...992f221

This PR addresses the root cause of incident-28477, caused by CentOS dropping their legacy mirrorlist and thus breaking our e2e tests.

We created a new CentOS 7 x86 AMI with the updated mirrorlist, this PR uses it for both e2e and kitchen tests.

This PR also marks a test as flaky.

[pr-commenter]

Regression Detector

Regression Detector Results

Run ID: 25906298-af31-4016-8a40-e8c23fae7310 Metrics dashboard Target profiles

Baseline: 8779d4a
Comparison: bcb16da

Performance changes are noted in the perf column of each table:

• ✅ = significantly better comparison variant performance
• ❌ = significantly worse comparison variant performance
• ➖ = no significant change in performance

No significant changes in experiment optimization goals

Confidence level: 90.00%
Effect size tolerance: |Δ mean %| ≥ 5.00%

There were no significant changes in experiment optimization goals at this confidence level and effect size tolerance.

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	links
➖	pycheck_1000_100byte_tags	% cpu utilization	+2.64	[-2.22, +7.50]	Logs
➖	basic_py_check	% cpu utilization	+1.67	[-0.94, +4.28]	Logs
➖	file_tree	memory utilization	+1.42	[+1.33, +1.51]	Logs
➖	idle	memory utilization	+0.43	[+0.40, +0.47]	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	+0.00	[-0.01, +0.01]	Logs
➖	uds_dogstatsd_to_api	ingress throughput	-0.00	[-0.00, +0.00]	Logs
➖	otel_to_otel_logs	ingress throughput	-0.01	[-0.82, +0.80]	Logs
➖	tcp_syslog_to_blackhole	ingress throughput	-0.14	[-13.05, +12.76]	Logs
➖	uds_dogstatsd_to_api_cpu	% cpu utilization	-2.06	[-2.93, -1.19]	Logs

Explanation

A regression test is an A/B test of target performance in a repeatable rig, where "performance" is measured as "comparison variant minus baseline variant" for an optimization goal (e.g., ingress throughput). Due to intrinsic variability in measuring that goal, we can only estimate its mean value for each experiment; we report uncertainty in that value as a 90.00% confidence interval denoted "Δ mean % CI".

For each experiment, we decide whether a change in performance is a "regression" -- a change worth investigating further -- if all of the following criteria are true:

1. Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.

2. Its 90.00% confidence interval "Δ mean % CI" does not contain zero, indicating that if our statistical model is accurate, there is at least a 90.00% chance there is a difference in performance between baseline and comparison variants.

3. Its configuration does not mark it "erratic".

[pr-commenter]

Test changes on VM

Use this command from test-infra-definitions to manually test this PR changes on a VM:

inv create-vm --pipeline-id=38089339 --os-family=ubuntu

Note: This applies to commit bcb16da

[pducolin]

/merge

[dd-devflow]

🚂 MergeQueue: pull request added to the queue

The median merge time in main is 25m.

Use /merge -c to cancel this operation!

[agent-platform-auto-pr]

The backport to 7.55.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-7.55.x 7.55.x
# Navigate to the new working tree
cd .worktrees/backport-7.55.x
# Create a new branch
git switch --create backport-27197-to-7.55.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 671f875b21bf84ec8b0d44cdd8cf1d450d808dc4
# Push it to GitHub
git push --set-upstream origin backport-27197-to-7.55.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-7.55.x

Then, create a pull request where the base branch is 7.55.x and the compare/head branch is backport-27197-to-7.55.x.