[ic-side-navigation] Move ic-badge from icon to right hand side of content

## Summary
Currently the `ic-badge` on an `ic-navigation-item` in an expanded `ic-side-navigation` is anchored to the icon. To bring in line with `ic-tabs` this should be moved to the right-hand side of the button.


ic-tabs example

This would also avoid future issues where the badge could overflow the button label if there were more content.

Start by locating the ic-side-navigation and ic-navigation-item implementation and styling, then compare the badge placement with ic-tabs. Done means the ic-badge appears on the right-hand side of the button content in expanded navigation and does not risk overlapping longer labels; no test file is named in the issue.

Written by the indexing model from the issue text.