Updated accessibility instructions to improve clarity and specificity regarding coding practices for accessibility, including keyboard navigation and semantic structure.
* add instructions for accessibility
* update readme
* Added a description to the a11y instructions
* Fix spelling and formatting issues
* Fixing line ending
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Co-authored-by: Michael Fairchild <mfairchild@microsoft.com>
Co-authored-by: Aaron Powell <me@aaron-powell.com>
