Add spacing between list items within info notes

[gosko]

When there is a list with class clean-list inside a Note component, list items are displayed with no padding between them which looks strange when longer list items are wrapped.

For example the following markup which is used on user profile pages (in certain conditions):

<div class="l-box note note--info" role="status" aria-labelledby="info-summary-title" tabindex="-1" data-component="info-summary" data-anchor="no">
<h2 id="info-summary-title" class="txt-saturn">Information</h2>
<ul class="clean-list" role="list">
<li>To maintain your affiliation with Adobe, please <a href="[...]">add your corporate email address to your account</a>.</li>
<li>To facilitate group operations and technical collaboration, please link your <a href="[...]">GitHub account</a>.</li>
</ul>
</div>

The two list items are displayed with no whitespace between them.

[vivienlacourba]

The same markup (a list with class clean-list) is used to display the summary of errors on a form but in that case the increased padding comes from the use of links pointing to the related form field. https://design-system.w3.org/styles/form-errors.html