[Fixes: GeoNode#7105] Remove HTML tags from visualization (GeoNode#7106)

* [Fixes: GeoNode#7015] Remove HTML tags from visualization

* [Fixes: GeoNode#7015] strip_tags removed inside model function, increase test coverage and fix template

(cherry picked from commit 9ac0741)

# Conflicts:
#	geonode/base/models.py
#	geonode/base/tests.py

geonode/base/models.py

@@ -40,7 +40,7 @@
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.staticfiles.templatetags import staticfiles
 from django.core.files.storage import default_storage as storage
-
+from django.utils.html import strip_tags
 from mptt.models import MPTTModel, TreeForeignKey
 
 from imagekit.models import ImageSpecField
@@ -883,14 +883,19 @@ def __init__(self, *args, **kwargs):
         super(ResourceBase, self).__init__(*args, **kwargs)
 
     def __str__(self):
-        return "{0}".format(self.title)
+        return str(self.title)
 
     def _remove_html_tags(self, attribute_str):
+        _attribute_str = attribute_str
         try:
             pattern = re.compile('<.*?>')
-            return re.sub(pattern, '', attribute_str)
+            _attribute_str = html.unescape(
+                re.sub(pattern, '', attribute_str).replace('\n', ' ').replace('\r', '').strip())
         except Exception:
-            return attribute_str
+            if attribute_str:
+                _attribute_str = html.unescape(
+                    attribute_str.replace('\n', ' ').replace('\r', '').strip())
+        return strip_tags(_attribute_str)
 
     @property
     def raw_abstract(self):