fix: handle spread props for inner components in Trans (#1869)

[cellog]

This fixes the case where we want to spread props on a component and adds test cases for both spread and for implicit true props

<Trans i18nKey="something">
  <Some {...spreadProps}>hi</Some>
</Trans>

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

Checklist (for documentation change)

• only relevant documentation part is changed (make a diff before you submit the PR)
• motivation/reason is provided
• commit message and code follows the Developer's Certification of Origin

[coveralls]

coverage: 97.678% (+0.08%) from 97.601%
when pulling b53e6a3 on cellog:issue-1869-spread
into a5287b5 on i18next:master.

[adrai]

included in v16.1.6