Fixed #34140 -- Reformatted code blocks in docs with blacken-docs.

docs/howto/legacy-databases.txt

@@ -58,9 +58,10 @@ each table's creation, modification, and deletion::
     class Person(models.Model):
         id = models.IntegerField(primary_key=True)
         first_name = models.CharField(max_length=70)
+
         class Meta:
-           managed = False
-           db_table = 'CENSUS_PERSONS'
+            managed = False
+            db_table = "CENSUS_PERSONS"
 
 If you do want to allow Django to manage the table's lifecycle, you'll need to
 change the :attr:`~django.db.models.Options.managed` option above to ``True``