Switch NullBooleanFields to BooleanFields, add conditional display of last question

apps/map/models.py

@@ -891,13 +891,11 @@ class CaseStudy(models.Model):
     )
 
     # 3.2.7
-    wants_conversation_with_ojuso = models.NullBooleanField(
+    wants_conversation_with_ojuso = models.BooleanField(
         verbose_name=_("Would you like to have a conversation with the ojuso team?"),
         help_text=_("This would be a conversation about challenging or engaging related developers, companies and \
                     investors."),
-        default=None,
-        null=True,
-        blank=True
+        default=True
     )
 
     ##
@@ -953,12 +951,9 @@ class CaseStudy(models.Model):
     )
 
     # 4.4
-    shown_on_other_platforms = models.NullBooleanField(
+    shown_on_other_platforms = models.BooleanField(
         verbose_name=_("Show on other platforms?"),
         help_text=_("Tick the box if you would like us to show this case study on other social media platforms"),
-        default=None,
-        null=True,
-        blank=True
     )
 
     # 4.4.1