12237 update to Django 4.2 / psycopg3 (#12916)

* 12237 upgrade django and psycopg

* 12237 add migration

* 12237 rename migration

* 12237 update requirements

* 12237 fix migration

* Update base requirements

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Co-authored-by: Jeremy Stretch <jstretch@netboxlabs.com>

netbox/core/models/data.py

@@ -290,8 +290,10 @@ class DataFile(models.Model):
 
     @property
     def data_as_string(self):
+        if not self.data:
+            return None
         try:
-            return self.data.tobytes().decode('utf-8')
+            return bytes(self.data, 'utf-8')
         except UnicodeDecodeError:
             return None