Add link to the GitHub repository behind the page

[dellagustin-sap]

This will enable users to easily find how to contribute to the page.

It could possibly be done with https://jekyll.github.io/github-metadata/site.github/ using site.github.repository_url and other similar fields.

[dellagustin-sap]

tested with adding this to _includes/navigation.html:

    {% if site.github != nil %}
    <li class="nav-item">
      <a href="{{ site.github.repository_url }}" class="nav-item nav-link text-light active"><i class="fab fa-github"></i> {{ site.github.repository_nwo }}</a>
    </li>
    {% endif %}

and this to _config.yml, to simulate the necessary fields from https://jekyll.github.io/github-metadata/site.github/ when running locally:

# Uncomment the lines below for local testing of https://jekyll.github.io/github-metadata/site.github/
github:
  repository_url: https://github.com/InnerSourceCommons/working-group-roles
  repository_nwo: InnerSourceCommons/working-group-roles

Result (focus on the header):

How it currently is, for comparison (+ backlink: InnerSource Commons, https://innersourcecommons.org/community/ at _config.yml on the screenshot above):

@rrrutledge , I could apply this to our fork at https://github.com/InnerSourceCommons/working-group-roles, if it is not included upstream.

Note: The change as described in this comment is not backwards compatible, the feature is turned on by default.

[rrrutledge]

I like it- it is a good idea.