fix: division by zero leads to NaN for coverage

Author: tommytroen

internal/vulnerability/queries.go

@@ -324,6 +324,7 @@ func GetVulnerabilitySummary(ctx context.Context, s slug.Slug, filter *TeamVulne
 	ret := &TeamVulnerabilitySummary{
 		TeamSlug: s,
 	}
+
 	for _, ws := range wSums {
 		ret.Critical += ws.Summary.Critical
 		ret.High += ws.Summary.High
@@ -335,7 +336,9 @@ func GetVulnerabilitySummary(ctx context.Context, s slug.Slug, filter *TeamVulne
 			ret.BomCount++
 		}
 	}
-	ret.Coverage = float64(ret.BomCount) / float64(len(wSums)) * 100
+	if ret.BomCount > 0 {
+		ret.Coverage = float64(ret.BomCount) / float64(len(wSums)) * 100
+	}
 
 	return ret, nil
 }