Add position field for passages

Signed-off-by: Emmy D'Anello <emmy.danello@animath.fr>

draw/models.py

@@ -375,10 +375,11 @@ class Pool(models.Model):
                 [4, 1, 2],
             ]
 
-        for line in table:
+        for i, line in enumerate(table):
             # Create the passage
             await Passage.objects.acreate(
                 pool=self.associated_pool,
+                position=i + 1,
                 solution_number=tds[line[0]].accepted,
                 defender=tds[line[0]].participation,
                 opponent=tds[line[1]].participation,