Fix crash while trying to upload final thesis as supervisor

Caused by a missing @Transactional

core/src/main/java/se/su/dsv/scipro/finalthesis/FinalThesisServiceImpl.java

@@ -56,6 +56,7 @@ public class FinalThesisServiceImpl extends AbstractServiceImpl<FinalThesis, Lon
     }
 
     @Override
+    @Transactional
     public FinalThesis upload(ProjectFileUpload fileUpload, String englishTitle, String swedishTitle) {
         ProjectFile fileDescription = storeFinalThesisFile(fileUpload);
         final FileReference reference = fileService.createReference(fileDescription.getFileDescription());