[experiments][migrations] Fix print statements

beat/web/experiments/migrations/0005_scheduler_addons_4.py

@@ -74,7 +74,7 @@ def reset_blocks(apps, schema_editor):
         if xp.errors:
             message = "The experiment `%s' isn't valid (skipping " \
                 "block update), due to the following errors:\n  * %s"
-            print message % (fullname, '\n * '.join(xp.errors))
+            print(message % (fullname, '\n * '.join(xp.errors)))
             continue
 
         # Loads the experiment execution description, creating the Block's,

beat/web/experiments/migrations/0006_block_order.py

@@ -66,7 +66,7 @@ def set_block_order(apps, schema_editor):
         if xp.errors:
             message = "The experiment `%s' isn't valid (skipping " \
                 "block update), due to the following errors:\n  * %s"
-            print message % (fullname, '\n * '.join(xp.errors))
+            print(message % (fullname, '\n * '.join(xp.errors)))
             continue
 
         # Goes, in order, setting block inner order