Fixed minor typos.
bug #4164 Fixed minor typos. (ahsio)

This PR was merged into the 2.3 branch.

Discussion
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Fixed minor typos.

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all (or 2.3+)
| Fixed tickets |

Commits
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da441ae Fixed minor typos.