Consistent with other places

Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/html/project.html

@@ -156,7 +156,7 @@
   <tr>
   <th>{% trans "Username" %}</th>
   <th>{% trans "Full name" %}</th>
-  <th>{% trans "Email" %}</th>
+  <th>{% trans "E-mail" %}</th>
   </tr>
   </thead>
   <tbody>