feat: Trans interpolating self-closing tags in components prop(object)

[abbudao]

This PR intends to close #1136. It provides:

1. More versatility to the Trans component as now is possible to interpolate self-closing tags
2. Updated Trans typing, reflecting the alternative usage described in docs.
3. Improved readability on mapAst's reducer.

The third point is opinionated, but I was having trouble to reason with it the way it was written.
I was also forced to write the pushTranslatedJSX function (still unsure if this is the best name though) to keep the DRY principle.

Checklist

• only relevant code is changed (make a diff before you submit the PR)
• run tests npm run test
• tests are included
• documentation is changed or added

[coveralls]

Coverage increased (+0.08%) to 95.682% when pulling 3c9d55b on abbudao:trans-components-self-closing into d0d44a5 on i18next:master.

[jamuhl]

thank you....was published in react-i18next@11.7.0