corrected keyboard-accessibility for input element

[stephaniequintana]

On the <input> element - changed display: none; to class="visually-hidden" and added focus to <label> element. (Utilizing opacity: 0 does not take the element out of the flow and thus caused spacing issues)

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[gitpod-io[bot]]

[stephaniequintana]

@jywarren, @TildaDares, @cesswairimu - Correcting this accessibility issue has helped me to identify other areas that need A11y attention. I will add these to my planning issues.