Fix vulnerability report filter dropdown button text truncation

What does this MR do?

On the vulnerability report page, there is a collection of filter dropdowns:

When the text in the dropdown button is too long, it's truncated. Previously, this truncation was happening at the end of the string. When multiple items are selected, the words +x more was also getting truncated, but it needs to show in its entirety. This MR fixes that issue.

Before	After

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Does this MR meet the acceptance criteria?

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