Prevent CI from running on both push and pull_request events

[KaanOzkan]

Motivation

Duplicate CI runs waste resources

Implementation

Push events will only be triggered on main. As a result pushes to your branches without a PR will not trigger a build.

Tests

[paracycle]

I am not sure if the reasoning is correct. AFAIK, the pull_request build runs against a merge commit of the current branch onto the current state of main which gives you more confidence that your PR won't cause a conflict if merged to main at that point in time.

So, there is a separate value we get from pull_request builds.

Ref: https://docs.github.com/en/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows#pull_request

Note that GITHUB_SHA for this event is the last merge commit of the pull request merge branch. If you want to get the commit ID for the last commit to the head branch of the pull request, use github.event.pull_request.head.sha instead.

[KaanOzkan]

Updated the configuration to favour pull_request builds by default instead. As a result pushed branches without a PR don't trigger CI.

[paracycle]

Thanks!

[paracycle]

Updated the configuration to favour pull_request builds by default instead. As a result pushed branches without a PR don't trigger CI.

Except pushes to main