Only show authors' email addresses if so configured in git-authors (#6494)

Honour the git-authors plugin's setting to render the authors' names
as links pointing to their email address:

* If the git-authors plugin is enabled and its show_email_address
  option is not set, or is set to true, render the author's name as a
  "mailto:" link.
* If the git-authors plugin is enabled and its show_email_address
  option is set to false, render the author's name in plain text with
  no link.
* If the git-authors plugin is not enabled (or not installed), don't
  show author information.

material/templates/partials/source-file.html

@@ -18,6 +18,7 @@
   </span>
 {% endmacro %}
 {% macro render_authors(authors) %}
+  {% set git_authors = config.plugins.get("git-authors") %}
   <span class="md-source-file__fact">
     <span class="md-icon" title="{{ lang.t('source.file.contributors') }}">
       {% if authors | length == 1 %}
@@ -28,9 +29,13 @@
     </span>
     <nav>
       {% for author in authors %}
+        {%- if git_authors.config.show_email_address %}
         <a href="mailto:{{ author.email }}">
           {{- author.name -}}
         </a>
+        {%- else -%}
+          {{- author.name -}}
+        {% endif -%}
         {%- if loop.revindex > 1 %}, {% endif -%}
       {% endfor %}
     </nav>

src/templates/partials/source-file.html

@@ -44,6 +44,7 @@
 
 <!-- Render authors -->
 {% macro render_authors(authors) %}
+  {% set git_authors = config.plugins.get("git-authors") %}
   <span class="md-source-file__fact">
     <span class="md-icon" title="{{ lang.t('source.file.contributors') }}">
       {% if authors | length == 1 %}
@@ -54,9 +55,13 @@
     </span>
     <nav>
       {% for author in authors %}
+        {%- if git_authors.config.show_email_address %}
         <a href="mailto:{{ author.email }}">
           {{- author.name -}}
         </a>
+        {%- else -%}
+          {{- author.name -}}
+        {% endif -%}
         {%- if loop.revindex > 1 %}, {% endif -%}
       {% endfor %}
     </nav>