Allow iterable ReactI18NextChildren as children

[nicegamer7]

Fixes issues where interpolations alongside other HTML element children would trigger TypeScript errors. Added tests to make sure this stays working.

Note: I went with React 18 typings becuase React 16 typings allowed for objects to be passed as children, which made it hard to test that our allowObjectInHTMLChildren option was working correctly. This shouldn't affect end-users since it's a development dependency.

Checklist

• only relevant code is changed (make a diff before you submit the PR)
• run tests npm run test
• tests are included
• commit message and code follows the Developer's Certification of Origin

[coveralls]

coverage: 96.173%. remained the same when pulling 381b227 on nicegamer7:hotfix/react-children into 056a85e on i18next:master.

[adrai]

fyi: @YutaMoriJP

[adrai]

thank you @nicegamer7
v13.2.1

[nicegamer7]

No worries :)

[YutaMoriJP]

@adrai @nicegamer7 Thanks you two 🙏