Release tooling: Don't cancel non-patch preparation when triggered manually

[JReinhold]

What I did

The non-patch PR preparation workflow will usually cancel any preparation if it doesn't find any changes to release. However there are instances where it might be valuable to prepare a release PR even though there are changes. Currently we have 7.5.0-alpha.7 released and we want to promote that to 7.5.0 without any extra changes - the cancellation would block that from being possible.

This PR makes it so that if the preparation is triggered manually, it will skip the "has changes" check entirely, similar to what it already does when it checks if a prepared PR is frozen with the freeze label.

Checklist for Contributors

Testing

The changes in this PR are covered in the following automated tests:

• stories
• unit tests
• integration tests
• end-to-end tests

Manual testing

This section is mandatory for all contributions. If you believe no manual test is necessary, please state so explicitly. Thanks!

Documentation

• Add or update documentation reflecting your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Checklist for Maintainers

• When this PR is ready for testing, make sure to add ci:normal, ci:merged or ci:daily GH label to it to run a specific set of sandboxes. The particular set of sandboxes can be found in code/lib/cli/src/sandbox-templates.ts

• Make sure this PR contains one of the labels below:

  Available labels

  • bug: Internal changes that fixes incorrect behavior.
  • maintenance: User-facing maintenance tasks.
  • dependencies: Upgrading (sometimes downgrading) dependencies.
  • build: Internal-facing build tooling & test updates. Will not show up in release changelog.
  • cleanup: Minor cleanup style change. Will not show up in release changelog.
  • documentation: Documentation only changes. Will not show up in release changelog.
  • feature request: Introducing a new feature.
  • BREAKING CHANGE: Changes that break compatibility in some way with current major version.
  • other: Changes that don't fit in the above categories.

🦋 Canary release

This PR does not have a canary release associated. You can request a canary release of this pull request by mentioning the @storybookjs/core team here.

core team members can create a canary release here or locally with gh workflow run --repo storybookjs/storybook canary-release-pr.yml --field pr=<PR_NUMBER>

[JReinhold]

Self-merging

[JReinhold]

See this run triggered by merging this PR being cancelled: https://github.com/storybookjs/storybook/actions/runs/6526270460/job/17719841163

And the run manually triggered just after, finishing successfully: https://github.com/storybookjs/storybook/actions/runs/6526289725/job/17719877966