fix comment

Author: arturobernalg

impl/maven-core/src/main/java/org/apache/maven/internal/impl/DefaultTempFileService.java

@@ -132,8 +132,10 @@ public void cleanup(final Session session) throws IOException {
             } catch (final IOException e) {
                 if (first == null) {
                     first = e;
+                } else if (e != first) {
+                    first.addSuppressed(e);
                 }
-                LOGGER.warn("Failed to delete temp path {}: {}", path, e.getMessage());
+                LOGGER.warn("Failed to delete temp path {}", path, e);
             }
         }
         bucket.clear();