Branches: Show MR popover on hover of MR badge
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# Context
In the Issues pages, whenever a user hovers over an MR link, an information-rich popover appears with useful info about the related MR.
However, when users hover over the MR badge in the Branches page, this popover does not appear. This is a missed opportunity to provide users with information that could be useful in context, and make our platform more consistent between products.
<table>
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<th>Hovering over an MR link in Issues</th>
<th>Hovering over an MR badge in Branches page</th>
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{width=2095 height=1202}
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<td>

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# Design proposal
When a user hovers over the MR badge in the Branches page, show the MR popover currently used in Issues pages.

issue