Cosmetic changes and spell-checking

[nikosbosse]

Description

This PR cleans up the stray half-sentence and new lines from a previous PR (#776) in the "Deprecated functions"-vignette. I also sprinkled in some spell-checking here and there :)

Checklist

• [ ] My PR is based on a package issue and I have explicitly linked it.
• [ ] I have included the target issue or issues in the PR title as follows: issue-number: PR title
• [ ] I have tested my changes locally.
• [ ] I have added or updated unit tests where necessary.
• [x] I have updated the documentation if required.
• [x] I have built the package locally and run rebuilt docs using roxygen2.
• [x] My code follows the established coding standards and I have run lintr::lint_package() to check for style issues introduced by my changes.
• [ ] I have added a news item linked to this PR.
• [ ] I have reviewed CI checks for this PR and addressed them as far as I am able.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 95.53%. Comparing base (15ffa26) to head (f4d95e1).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #779 +/- ## ======================================= Coverage 95.53% 95.53% ======================================= Files 21 21 Lines 1567 1567 ======================================= Hits 1497 1497 Misses 70 70 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.