enhancement: anchor and icon restructuring

[stefanoScalzo]

Is this a bug, enhancement, or feature request?

feature request

Briefly describe your proposal.

The hover and focus does not change the whole background color but only the anchor OR icon. In order to fix this we need to add the span icon inside of the anchor.

Which versions of Vue.JS and Fundamental Vue are affected? (If this is a feature request, use current version.)

v0.18.1

Please provide relevant source code if applicable.

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