Module objective in README.md should not be a quote

Problem/Motivation

The module objective in the README.md has a ">" character before the objective. This makes it a quote in the Markdown viewer.

Steps to reproduce

Go to https://git.drupalcode.org/project/menu_link_attributes/-/blob/8.x-1.x/R... and see the quote formatting being applied.

Proposed resolution

Remove the ">" character

Remaining tasks

Implement. Commit. Enjoy!

User interface changes

None.

API changes

None

Data model changes

None.