Remove closing tag comments in template files.

Some of Bartik's Twig templates contain comments indicating the closing tags for each HTML element in the template.
For example here is the end of the page.html.twig file...

          </div> <!-- /#footer -->
        {% endif %}
      </footer> <!-- /.section -->
    </div> <!-- /#footer-wrapper -->
  </div> <!-- /#page -->
</div> <!-- /#page-wrapper -->

No other theme follows this practice and with work such as #1903048: Revise Bartik template indentation inline with best practices. you can clearly see from just structuring the code correctly what belongs to what.

These comments also print in the frontend when you look at the markup. It looks like we haven't tidied up after ourselves and we want to show a good example with Bartik.

Please can the <!--/ .... > comments be removed.

Beta phase evaluation

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