Update GitHub Actions to v3 and rename workflow

[mraible]

The renaming to main.yml is based on my recent experience. build.yml is another good alternative, IMO.

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Please make sure the below checklist is followed for Pull Requests.

• All continuous integration tests are green
• Tests are added where necessary
• The JDL part is updated if necessary
• jhipster-online is updated if necessary
• Documentation is added/updated where necessary
• Coding Rules & Commit Guidelines as per our CONTRIBUTING.md document are followed

When you are still working on the PR, consider converting it to Draft (below reviewers) and adding skip-ci label, you can still see CI build result at your branch.

[mshima]

We probably should keep the template as github-actions or put at the correct path.
Otherwise main.yml is too generic.

WDYT?

[mraible]

@mshima I agree that main.yml might be too generic for the generator-jhipster project. However, I think it's appropriate to name it main.yml (or build.yml) in the generated project.

[mshima]

@mshima I agree that main.yml might be too generic for the generator-jhipster project. However, I think it's appropriate to name it main.yml (or build.yml) in the generated project.

Sure. That’s what I mean. Keep the template as github-actions.yml and rename.