Remove duplicate entry in 'Features' summary

[tpwo]

Hi, I noticed that two bullet points in Features on the docs page tell the same thing using different words:

• Ensure that there is exactly one newline at the end of each file, to comply with the POSIX standard.
• Ensure a \n exists at the end of the file.

I guess that the latter can be removed.

Checklist

• N/A Add test cases to all the changes you introduce
• Update the documentation for the changes

[coveralls]

Pull Request Test Coverage Report for Build 4812745808

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 99.798%

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Totals
Change from base Build 4595856345:	0.0%
Covered Lines:	493
Relevant Lines:	494

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💛 - Coveralls

[lyz-code]

Hey @wojdatto thanks for taking the time to open a PR and fix the docs <3