feat: Switch FormattedDate component to Intl.DateTimeFormat

[KuSh]

Summary

Use Intl.DateTimeFormat instead of fixed momentjs format in FormattedDate component

This comes from a discussion in i18n - Localization channel in mattermost community where Ian Liu reported bad date formatting for Chinese and Japanese languages. After some digging it appeared there were more problems than that and I suggested to switch from momentjs to Intl.DateTimeFormat

Ticket Link

Checklist

• [x] Added or updated unit tests (required for all new features)
• [x] Has UI changes
• [x] Includes text changes and localization file updates
• [x] Have tested against the 5 core themes to ensure consistency between them.
• [ ] Have run E2E tests by adding label E2E iOS tests for PR.

Device Information

This PR was tested on: Android Emulator - Nexus 8 API 31 and OnePlus 6 running /e/OS 2.4.1-t

Screenshots

English	Japanese	French

Release Note

Rework date format to respect languages and regions specificities

[mattermost-build]

Hello @KuSh,

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[enahum]

Maybe should consider adding an end to end test or unit tests to make sure this does not break again

[larkox]

@KuSh I see many stylistic changes that do not completely conform with our codebase. Do you mind removing the stylistic changes so the PR is clearer?

[KuSh]

@KuSh I see many stylistic changes that do not completely conform with our codebase. Do you mind removing the stylistic changes so the PR is clearer?

Sure, I tried to configure prettier to follow you codebase / eslint but it seems I didn't succeed :/

[KuSh]

@larkox I've removed stylistic changes

[KuSh]

@rahimrahman I've pushed the requested changes!