Removes extra line from group issues list actions menu

What does this MR do and why?

Checks if additional items are present before showing divider. Avoids showing line on Group issues list when there are not items to divide.

Screenshots or screen recordings

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	Before	After
Group issues
Project issues (unchanged; for reference)

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

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