fix ReadOnlyZipStore::list

Author: brokkoli71

src/main/java/dev/zarr/zarrjava/store/ReadOnlyZipStore.java

@@ -140,7 +140,9 @@ public Stream<String[]> list(String[] keys) {
                 if (entryName.startsWith("/")) {
                     entryName = entryName.substring(1);
                 }
-
+                if (entryName.endsWith("/")) {
+                    entryName = entryName.substring(0, entryName.length() - 1);
+                }
                 if (!entryName.startsWith(prefix) || entryName.equals(prefix)) {
                     continue;
                 }