Fix Immutable List to Mutable List (cBioPortal#10639)

src/main/java/org/cbioportal/service/impl/StudyViewServiceImpl.java

@@ -394,7 +394,7 @@ public List<GenomicDataCountItem> getCNAAlterationCountsByGeneSpecific(List<Stri
                         genomicDataCount.setCount(count);
 
                         return genomicDataCount;
-                    }).toList();
+                    }).collect(Collectors.toList());
 
                 int totalCount = genomicDataCounts.stream().mapToInt(GenomicDataCount::getCount).sum();
                 int naCount = sampleIds.size() - totalCount;