GitHub Workflows security hardening

[sashashura]

This PR adds explicit permissions section to workflows. This is a security best practice because by default workflows run with extended set of permissions (except from on: pull_request from external forks). By specifying any permission explicitly all others are set to none. By using the principle of least privilege the damage a compromised workflow can do (because of an injection or compromised third party tool or action) is restricted.
It is recommended to have most strict permissions on the top level and grant write permissions on job level case by case.

[LeoDog896]

LGTM! This PR is very important -- you may want to request reviews from the contributors for this.

[SethFalco]

Thanks for the explanation and resources! I'd actually read into the topic before, but didn't see the use for it at the time. Especially as actions/checkout and GitHub's own repositories don't configure these permissions for their workflows either.

I suppose the main benefit for us is that if we do accidentally merge a malicious pull request, it minimizes the damage that can be done on a push event later. For example, if main ends up directly or indirectly installing a vulnerable or compromised npm package after updating direct dependencies.