Dropdown's menu list update

[GomezIvann]

Checklist

• Build process is done without errors and all tests pass in the /lib directory.
• Self-reviewed the code before submitting.
• Meets accessibility standards.
• Added/updated documentation to /website as needed.
• Added/updated tests as needed.

Description

Dropdown Menu

The adopted solution is:

• The menu's minimum width will be the maximum option length (min-width: "min-content").
• If the button is longer than that minimum width, it will increase to match the current width of the button (width: "Npx", being N the width of the button trigger).

Header Dropdown

The dropdown in the Header had a special container for styling, which was overflowing the header's intrinsic height. To fix this, I add a display: flex, which by default always tries to fit the parent element that contains it.

Screenshots

Closes #1438 and #1451