[TEST] Don't use extraFS files as legacy files in tests

Author: s1monw

src/test/java/org/elasticsearch/index/store/StoreTest.java

@@ -270,7 +270,7 @@ public void testWriteLegacyChecksums() throws IOException {
         Store.LegacyChecksums checksums = new Store.LegacyChecksums();
         Map<String, StoreFileMetaData> legacyMeta = new HashMap<>();
         for (String file : store.directory().listAll()) {
-            if (file.equals("write.lock") || file.equals(IndexFileNames.OLD_SEGMENTS_GEN)) {
+            if (file.equals("write.lock") || file.equals(IndexFileNames.OLD_SEGMENTS_GEN) || file.startsWith("extra")) {
                 continue;
             }
             BytesRef hash = new BytesRef();