[ENG-9805] implement asc sorting for admin brand tab (case insensitive) (CenterForOpenScience#11591)

* implement asc sorting for admin brand tab (case insensitive)

* Fix indentation in brand list template

Author: mkovalua

admin/templates/brands/list.html

@@ -21,7 +21,7 @@ <h2>List of Brands</h2>
         </tr>
     </thead>
     <tbody>
-    {% for brand in brands|dictsort:"name" %}
+    {% for brand in brands|dictsort:"name_lower" %}
     <tr>
         <td><a href="{% url 'brands:detail' brand_id=brand.id %}">{{ brand.name }}</a></td>
         <td>{{ brand.get_provider_types }}</td>

osf/models/brand.py

@@ -25,6 +25,10 @@ class Meta:
     secondary_color = models.CharField(max_length=7)
     background_color = models.CharField(max_length=7, blank=True, null=True)
 
+    @property
+    def name_lower(self):
+        return self.name.lower() if self.name else ''
+
     def get_provider_types(self):
         unique_types = self.providers.values_list('type', flat=True).distinct()
         results = []