Set default cadences automatic to false

What does this MR do?

We are creating a default iteration cadence behind the scenes, which is currently wrongly set to automatic. This MR fixes the automatic to false and also migrations any of the existing automatic=true records to automatic=false

We still want to keep the automatic=true as default column value, which will be useful when we reveal the cadences to the user, and the user would be able to turn it off.

Database

Affected records: ~700

explain select id from iterations_cadences where automatic=true
Seq Scan on public.iterations_cadences  (cost=0.00..135.43 rows=669 width=8) (actual time=0.010..0.777 rows=696 loops=1)
   Filter: iterations_cadences.automatic
   Rows Removed by Filter: 1274
   Buffers: shared hit=29

UP

== 20210317104032 SetIterationCadenceAutomaticToFalse: migrating ==============
== 20210317104032 SetIterationCadenceAutomaticToFalse: migrated (0.0719s) =====

DOWN

== 20210317104032 SetIterationCadenceAutomaticToFalse: reverting ==============
== 20210317104032 SetIterationCadenceAutomaticToFalse: reverted (0.0000s) =====

Update statement

Running update statement on database-lab

exec UPDATE "iterations_cadences" SET "automatic" = FALSE WHERE "iterations_cadences"."automatic" = TRUE
Session: 2779
The query has been executed. Duration: 0.000 s (edited)

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

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