Fix typos and linguistic errors in documentation

[survivant]

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Please make sure the below checklist is followed for Pull Requests.

• [X ] All continuous integration tests are green
• [ X] Tests are added where necessary
• [ X] The JDL part is updated if necessary
• [ X] jhipster-online is updated if necessary
• [ X] Documentation is added/updated where necessary
• [ X] Coding Rules & Commit Guidelines as per our CONTRIBUTING.md document are followed

When you are still working on the PR, consider converting it to Draft (below reviewers) and adding skip-ci label, you can still see CI build result at your branch.

[qmonmert]

👍

[survivant]

if you want can you add this label to this PR : hacktoberfest-accepted