ci: Run unit tests on main

[ko3n1g]

What does this PR do ?

For unit test coverage, we need a baseline against which we can compare a PR. This baseline should come from branch main. So this PR allows running unit tests only on push to main. Therefore, with each merge of a PR we will now run the unit test suite on main. However, we have concurrency control activated so if multiple PRs get merged within a short span old runs will be cancelled prematurely so that only for the most recent merge/push to main a workflow is running.

After unit tests finish on main, we compute, aggreate and upload coverage results of main.

This can later be used by PRs. PRs will compute their own coverage result, download the baseline of main and compare against.

NOTE: Comparing against main can only be activated in cicd-main.yml after we have merged this PR.

Pipelines:

• PR workflow still works: https://github.com/NVIDIA/NeMo/actions/runs/13028978890
• Push workflow runs unit tests only: https://github.com/NVIDIA/NeMo/actions/runs/13028859234

Collection: [Note which collection this PR will affect]

Changelog

• Add specific line by line info of high level changes in this PR.

Usage

• You can potentially add a usage example below

# Add a code snippet demonstrating how to use this 

GitHub Actions CI

The Jenkins CI system has been replaced by GitHub Actions self-hosted runners.

The GitHub Actions CI will run automatically when the "Run CICD" label is added to the PR.
To re-run CI remove and add the label again.
To run CI on an untrusted fork, a NeMo user with write access must first click "Approve and run".

Before your PR is "Ready for review"

Pre checks:

• Make sure you read and followed Contributor guidelines
• Did you write any new necessary tests?
• Did you add or update any necessary documentation?
• Does the PR affect components that are optional to install? (Ex: Numba, Pynini, Apex etc)
  • Reviewer: Does the PR have correct import guards for all optional libraries?

PR Type:

• New Feature
• Bugfix
• Documentation

If you haven't finished some of the above items you can still open "Draft" PR.

Who can review?

Anyone in the community is free to review the PR once the checks have passed.
Contributor guidelines contains specific people who can review PRs to various areas.

Additional Information

• Related to # (issue)

[github-actions]

[🤖]: Hi @ko3n1g 👋,

We wanted to let you know that a CICD pipeline for this PR just finished successfully

So it might be time to merge this PR or get some approvals

I'm just a bot so I'll leave it you what to do next.

//cc @pablo-garay @ko3n1g

[codecov-commenter]

Welcome to Codecov 🎉

Once you merge this PR into your default branch, you're all set! Codecov will compare coverage reports and display results in all future pull requests.

Thanks for integrating Codecov - We've got you covered ☂️