[Feature Request]: Add developer options menu support for creating multiple profiles

[BenHenning]

Is your feature request related to a problem? Please describe.

Sometimes we want to demo (in the case of onboarding changes in today's CLaM meeting) or test scenarios with multiple profiles, but adding profiles is very tedious:

1. Select add profile.
2. Input admin pin.
3. Input profile name.
4. Click add.

Describe the solution you'd like

I think 3 new options should be added to the developer options menu:

• Generate 1 profile.
• Generate 3 profiles (in case the user wants to get to the max of 10 quickly).
• Delete all non-admin profiles (to be able to reset back to the single account state without having to delete profiles one-by-one).

The profile names can be auto-generated (ideally from a predetermined list of 9 names to pick to keep it a bit more personable than "Profile 1", etc.), and no profile pins.

Describe alternatives you've considered

I thought about having an option for inputting the number of profiles with an 'add' button, but that seems like it would be a bit unwieldy.

Additional context

This is a developer option (i.e. part of the developer options menu and not visible in non-developer builds). We also have a test-only utility for adding profiles that could probably be used as a reference for performing this work:

oppia-android/testing/src/main/java/org/oppia/android/testing/profile/ProfileTestHelper.kt

Line 12 in 1273c31

class ProfileTestHelper @Inject constructor(

This also came up from a demo of onboarding changes by @adhiamboperes.