fix(ci): fix Splunk integration test flakiness and re-enable

[thomasqueirozb]

Summary

Fixes #23474 - Splunk integration tests were timing out due to two issues:

1. Incorrect volume path in compose.yaml (introduced during integration test reorganization)
2. Missing health check causing tests to start before Splunk was ready

Vector configuration

NA

How did you test this PR?

• Verified the fix by running make check-clippy
• The changes address root causes identified from the issue

Change Type

• Bug fix
• New feature
• Dependencies
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the no-changelog label to this PR.

References

• Closes: Splunk integration tests are failing #23474

[thomasqueirozb]

/ci-run-integration-splunk

[datadog-vectordotdev]

 

⚠️ Warnings

🚦 1 Pipeline job failed

Changelog | validate-changelog     

ℹ️ Info

No other issues found (see more)

🧪 All tests passed
❄️ No new flaky tests detected

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