Merge pull request #555 from RADAR-base/554-azure-storage-blob-upgrad…

…e-causes-failed-jobs

Fix issue #554

src/main/java/org/radarbase/output/source/AzureSourceStorage.kt

@@ -34,7 +34,7 @@ class AzureSourceStorage(
                 SimpleFileStatus(
                     Paths.get(it.name),
                     it.isPrefix ?: false,
-                    it.properties?.lastModified?.toInstant(),
+                    if (it.isPrefix) null else it.properties?.lastModified?.toInstant(),
                 )
             }
         }