Remove uoa experiment

[marcosholgado]

Task/Issue URL: https://app.asana.com/0/45878998844068/1200339867891418
Tech Design URL:
CC:

Description:
This PR removes all the code from the UOA experiment. In the task you can find two apks to facilitate testing.

Steps to test this PR:

Normal Update

1. Install the "develop" apk and launch the app.
2. Kill the app
3. Install the "new" apk and launch the app.
4. Wait 1 minute
5. You should not see the UOA notification and the app should not crash

Normal Update Not Crashing

1. Install the "develop" apk and launch the app.
2. Kill the app
3. Install the "new" apk and DO NOT launch the app.
4. Wait 1 minute
5. You should not see the UOA notification
6. The logcat should show an error because it couldn't find the worker but the app won't crash.

Class not found: com.duckduckgo.app.notification.NotificationScheduler$UseOurAppNotificationWorker

Notification showing

1. Install the "develop" apk and launch the app.
2. Wait 1 minute
3. You should see the UOA notification, do not dismiss the notification.
4. Install the "new" apk.
5. The notification should disappear

Database clean up

1. Install from the develop branch (not the apk)
2. Launch the app
3. In the database inspector add the following:
4. In the table userStage change the appStage to USE_OUR_APP_ONBOARDING
5. Open a new query and execute:
6. INSERT INTO user_events values ('USE_OUR_APP_SHORTCUT_ADDED', 1)
7. INSERT INTO user_events values ('USE_OUR_APP_FIREPROOF_DIALOG_SEEN', 1)
8. INSERT INTO dismissed_cta values ('USE_OUR_APP')
9. INSERT INTO dismissed_cta values ('USE_OUR_APP_DELETION')
10. Install the app from this branch
11. In the database inspector check the following:
12. In the table userStage the stage should be ESTABLISHED
13. The tables user_events and dismissed_cta should not contain anything related with UOA

Database clean up 2

1. Install from the develop branch (not the apk)
2. Launch the app
3. In the table userStage change the appStage to USE_OUR_APP_NOTIFICATION
4. Install the app from this branch
5. In the database inspector check the following:
6. In the table userStage the stage should be ESTABLISHED

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Internal references:

Software Engineering Expectations
Technical Design Template

[cmonfortep]

LGTM, nice work here @marcosholgado

Thanks for providing those apks, really helpful for testing.

[sloppyjuicy]

#1252