Updated new onboarding criteria

[MohitGupta121]

Explanation

Updated new onboarding criteria because sometimes 2 PRs can be small changes. And sometimes the contributor does not communicate well and will disappear soon. With that we see more new contributors so that we can keep growing the team, under the stricter acceptance criteria.

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: ...".)
• Any changes to scripts/assets files have their rationale included in the PR explanation.
• The PR follows the style guide.
• The PR does not contain any unnecessary code changes from Android Studio (reference).
• The PR is made from a branch that's not called "develop" and is up-to-date with "develop".
• The PR is assigned to the appropriate reviewers (reference).

[MohitGupta121]

@adhiamboperes PTAL, Thanks!

[adhiamboperes]

Thanks @MohitGupta121 LGTM.

[oppiabot]

Assigning @BenHenning for code owner reviews. Thanks!