Fix no-op assertion in ContentIdentifier index-key round-trip test (apache#4979)

The storageLocation test builds identifierFromKey via
indexKeyToIdentifier(identifier.toIndexKey()) to check the
IndexKey round-trip, but asserts identifierFromKey isEqualTo
identifierFromKey, comparing the value to itself. That is
vacuously true and never verifies the toIndexKey /
indexKeyToIdentifier serialization, so a regression there would
go undetected.

Assert against the original identifier so the test actually
covers the round-trip. The corrected assertion passes for all
parameterized inputs.

Author: anxkhn

persistence/nosql/persistence/metastore/src/test/java/org/apache/polaris/persistence/nosql/metastore/TestContentIdentifier.java

@@ -42,7 +42,7 @@ public void storageLocation(String input, List<String> elements) {
     soft.assertThat(identifier.elements()).containsExactlyElementsOf(elements);
     var inKey = identifier.toIndexKey();
     var identifierFromKey = ContentIdentifier.indexKeyToIdentifier(inKey);
-    soft.assertThat(identifierFromKey).isEqualTo(identifierFromKey);
+    soft.assertThat(identifierFromKey).isEqualTo(identifier);
   }
 
   static Stream<Arguments> storageLocation() {