[9.1] (backport #11327) Avoid downloading/uploading unnecessary artifacts in CI runs

[mergify]

What does this PR do?

Removes upload of build/** from integration tests steps since that would cause uploading everything (including subdirectories) under build/ including reuploading large elastic-agent packages (already uploaded at the packaging steps)

It also introduces more "precise" artifacts download from the packaging steps leveraging platform and package formats.

Why is it important?

To reduce wasted space and time in CI builds

Checklist

• I have read and understood the pull request guidelines of this project.
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in ./changelog/fragments using the changelog tool
• I have added an integration test or an E2E test

Disruptive User Impact

How to test this PR locally

Related issues

Questions to ask yourself

• How are we going to support this in production?
• How are we going to measure its adoption?
• How are we going to debug this?
• What are the metrics I should take care of?
• ...

---

This is an automatic backport of pull request #11327 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 3cedabf has failed:

On branch mergify/bp/9.1/pr-11327
Your branch is up to date with 'origin/9.1'.

You are currently cherry-picking commit 3cedabfc0.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   .buildkite/bk.integration.pipeline.yml

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[elasticmachine]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: 6f8c93e

Failed CI Steps

• x86_64:non-sudo: default - platform-ingest-elastic-agent-debian-11-1762801856
• x86_64:non-sudo: default - platform-ingest-elastic-agent-debian-11-1762801856
• x86_64:sudo: container - platform-ingest-elastic-agent-debian-13-1762801856
• x86_64:sudo: container - platform-ingest-elastic-agent-debian-13-1762801856
• x86_64:sudo: container - platform-ingest-elastic-agent-debian-13-1762801856

History

• 💔 Build #30812 failed e9d64af

cc @pchila