Remove email frequency early commit

files/db/update_v9_to_v10.sql

@@ -1,6 +1,5 @@
 ALTER TABLE users ADD COLUMN timezone char(64) AFTER language;
 ALTER TABLE users MODIFY COLUMN email VARCHAR(320) NOT NULL;
-ALTER TABLE users ADD COLUMN frequency VARCHAR(1) NOT NULL AFTER active;
-UPDATE users SET timezone = 'Europe/Paris', frequency = 'P';
+UPDATE users SET timezone = 'Europe/Paris';
 
 ALTER TABLE projects MODIFY COLUMN timezone char(64);