Fix Part of #4938: New onboarding flow gating platform param 1 of 3

[adhiamboperes]

Explanation

Fix Part of #4938: Introduce a new platform parameter that will be used to gate the revised onboarding flow during development.

Essential Checklist

• The PR title and explanation each start with "Fix #bugnum: " (If this PR fixes part of an issue, prefix the title with "Fix part of #bugnum: ...".)
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[adhiamboperes]

Hi @kkmurerwa, could you please take a look at this PR?

[kkmurerwa]

@adhiamboperes I have taken a look at the PR and have left a few comments. PTAL

[oppiabot]

Hi @adhiamboperes, I'm going to mark this PR as stale because it hasn't had any updates for 7 days. If no further activity occurs within 7 days, it will be automatically closed so that others can take up the issue.
If you are still working on this PR, please make a follow-up commit within 3 days (and submit it for review, if applicable). Please also let us know if you are stuck so we can help you!

[adhiamboperes]

@kkmurerwa, I have addressed your comments. PTAL.

[adhiamboperes]

Thanks @kkmurerwa!

@BenHenning, PTAL.

[BenHenning]

Thanks @adhiamboperes! This LGTM.

[BenHenning]

Deferring to you to merge @adhiamboperes since I'm not sure if you have any branched PRs coming after this that require special handling.

[oppiabot]

Hi @adhiamboperes, this PR is ready to be merged. Please address any remaining comments prior to merging, and feel free to merge this PR once the CI checks pass and you're happy with it. Thanks!