Multiplatform builds

[Zeitsperre]

Pull Request Checklist:

• This PR addresses an already opened issue (for bug fixes / features)
  • This PR fixes #xyz
• Tests for the changes have been added (for bug fixes / features)
  • (If applicable) Documentation has been added / updated (for bug fixes / features)

What kind of change does this PR introduce?

• Adds builds that do not compile with NetCDF to the main workflows
• Substitutes the GitHub Actions tags for commit hashes
• Adds the step-security/harden-runner action for reducing the attack surface of builds
• Adds macOS and Windows builds (macOS with and without NetCDF4)
• Adjusts the CMakeLists.txt to emit fewer warnings

Does this PR introduce a breaking change?

No.

Other information:

The commit hashes will be managed by Dependabot once that integration has been added to the repository.

[Zeitsperre]

@analytophile

This Pull Request is ready to be merged. The brief summary here is:

• Pull Requests and commits pushed to the main branch will now trigger both Debug and Release builds for all supported architectures.
• Failing builds in pull requests will prevent merging to main.

We should perform a "squash" of the commits to not pollute the git history when this is merged.

[Zeitsperre]

@analytophile Just wondering if there's anything needed in order to merge this. All this adds is build checks to ensure that Pull Requests are compiling Raven properly on multiple architecture.

[Zeitsperre]

@huard

This PR adds multiplatform builds to the CI. This does not prevent admins from pushing directly to the main branch. It also provides some small security fixes to the CI.

[huard]

Ideas on how to solve the failed checks ?
Maybe remove #define STANDALONE since it seems to be added by the compiler?

[Zeitsperre]

@huard I can try removing that, but I get the feeling that the issue stems from a missing variable. See #51.

[huard]

You're absolutely right.