docs: public static List<String> getBuildNumbersNotToBeDeleted(Run build) {
          List<String> notToDelete = Lists.newArrayList();
          List<? extends Run<?, ?>> builds = build.getParent().getBuilds();
          for (Run<?, ?> run : builds) {
              if (run.isKeepLog()) {
                  notToDelete.add(String.valueOf(run.getNumber()));
              }
          }
          return notToDelete;
      }