Add missing email templates

aleksis/core/templates/templated_email/data_checks.css

+body {
+    line-height: 1.5;
+    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
+    font-weight: normal;
+    color: rgba(0, 0, 0, 0.87);
+}
+
+.count {
+    text-align: right;
+    font-family: monospace;
+    font-size: 14pt;
+}
+
+td, th {
+    padding: 10px;
+}

aleksis/core/templates/templated_email/data_checks.email

+{% load i18n %}
+
+{% block subject %}
+ {% trans "The system detected some new problems with your data." %}
+{% endblock %}
+
+{% block plain %}
+ {% trans "Hello," %}
+
+ {% blocktrans %}
+  the system detected some new problems with your data.
+  Please take some time to inspect them and solve the issues or mark them as ignored.
+ {% endblocktrans %}
+
+ {% for result in results %}
+  {{ result.0.problem_name }}: {{ result.1 }}
+ {% endfor %}
+{% endblock %}
+
+{% block html %}
+ <style>
+  {% include "templated_email/data_checks.css" %}
+ </style>
+ <p>{% trans "Hello," %}</p>
+ <p>
+  {% blocktrans %}
+   the system detected some new problems with your data.
+   Please take some time to inspect them and solve the issues or mark them as ignored.
+  {% endblocktrans %}
+ </p>
+
+ <table>
+  <tr>
+   <th>{% trans "Problem description" %}</th>
+   <th>{% trans "Count of objects with new problems" %}</th>
+  </tr>
+  {% for result in results %}
+   <tr>
+    <td>{{ result.0.problem_name }}</td>
+    <td class="count">{{ result.1 }}</td>
+   </tr>
+  {% endfor %}
+ </table>
+{% endblock %}