Add set tenant method to demo app

[bhparijat]

Adding functionality for setting tenant in demo app in order to test TOTP MFA at tenant level

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[changeset-bot]

⚠️ No Changeset found

Latest commit: 5f0fdfd

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[google-oss-bot]

Size Report ¹

Affected Products

No changes between base commit (2857f04) and merge commit (b75a3fe).

Test Logs

• Base (2857f04): https://github.com/firebase/firebase-js-sdk/actions/runs/3641853244
• Merge (b75a3fe): https://github.com/firebase/firebase-js-sdk/actions/runs/3642760190

1. https://storage.googleapis.com/firebase-sdk-metric-reports/6k2tnGWq0j.html

[google-oss-bot]

Size Analysis Report ¹

Affected Products

No changes between base commit (2857f04) and merge commit (2e36ddf).

Test Logs

• Base (2857f04): https://github.com/firebase/firebase-js-sdk/actions/runs/3641853244
• Merge (2e36ddf): https://github.com/firebase/firebase-js-sdk/actions/runs/3642730348

1. https://storage.googleapis.com/firebase-sdk-metric-reports/gGDnPSNFL9.html