Wait for Tekton trigger metrics in E2E

[nubtron]

What does this PR do?

Adds a Cilium-style readiness wait to the Tekton E2E fixture so the test waits for Tekton Triggers controller metric families before running the Agent check.

Motivation

Test Agent release runs for 7.81 RCs are repeatedly failing only on Tekton with:

AssertionError: Needed at least 1 candidates for 'tekton.triggers_controller.clusterinterceptor', got 0

The controller is scrapeable and emits related workqueue/reconcile metrics, but the resource-count metric can be absent on the first scrape. This waits for the trigger resource count metric families that the E2E assertions require.

Review checklist

• Ran ddev --no-interactive test -fs tekton
• Validate with Test Agent release retry once merged/backported/tagged

[dd-octo-sts]

Validation Report

All 21 validations passed.

Show details

Validation	Description	Status
agent-reqs	Verify check versions match the Agent requirements file	✅
ci	Validate CI configuration and code coverage settings	✅
codeowners	Validate every integration has a CODEOWNERS entry	✅
config	Validate default configuration files against spec.yaml	✅
dep	Verify dependency pins are consistent and Agent-compatible	✅
http	Validate integrations use the HTTP wrapper correctly	✅
imports	Validate check imports do not use deprecated modules	✅
integration-style	Validate check code style conventions	✅
jmx-metrics	Validate JMX metrics definition files and config	✅
labeler	Validate PR labeler config matches integration directories	✅
legacy-signature	Validate no integration uses the legacy Agent check signature	✅
license-headers	Validate Python files have proper license headers	✅
licenses	Validate third-party license attribution list	✅
metadata	Validate metadata.csv metric definitions	✅
models	Validate configuration data models match spec.yaml	✅
openmetrics	Validate OpenMetrics integrations disable the metric limit	✅
package	Validate Python package metadata and naming	✅
qa-label	Validate the pull request declares whether it needs QA for the next Agent release	✅
readmes	Validate README files have required sections	✅
saved-views	Validate saved view JSON file structure and fields	✅
version	Validate version consistency between package and changelog	✅

View full run

[datadog-prod-us1-4]

 

🎉 All green!

🧪 All tests passed
❄️ No new flaky tests detected

🎯 Code Coverage (details)
• Patch Coverage: 33.33%
• Overall Coverage: 71.85%

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