Add recommendations on GitHub branch protection rules and/or a ruleset recipe to template

[matt-graham]

Is Your Feature Request Related to a Problem? Please Describe

@zmek who attended the Festival of Digital Research and Scholarship workshop asked about recommendations for setting up rulesets to protect main branch with regards to the tutorial we used there.

Describe the Solution You'd Like

I think having some recommendations around a good basic default branch protection rule might be useful (possibly require status checks + pull requests before merging?) and/or creating a ruleset JSON file similar to those in the ruleset-recipes repository Zella linked to that people could import to set up a minimal set of rules.

Describe Alternatives You've Considered

No response

Additional Context

No response