fix the wording in versionadded directives
minor #3832 fix the wording in versionadded directives (for the 2.3 branch) (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
----------

fix the wording in versionadded directives (for the 2.3 branch)

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets |

Commits
-------

a2d39a1 fix the wording in versionadded directives