RFR: 8345632: [ASAN] memory leak in get_numbered_property_as_sorted_string function

[SendaoYan]

Hi all,
This PR fix memory leak problem in get_numbered_property_as_sorted_string function which introduced by [JDK-8342089](https://bugs.openjdk.org/browse/JDK-8342089) when the function get_numbered_property_as_sorted_string `return nullptr`. Free the memory before `return nullptr`, risk is low.

Additional testing:

- [ ] jtreg tests (include tier1/2/3 etc.) on linux-x64
- [ ] jtreg tests (include tier1/2/3 etc.) on linux-aarch64

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Commit messages:
 - 8345632: [ASAN] memory leak in get_numbered_property_as_sorted_string function

Changes: https://git.openjdk.org/jdk/pull/22594/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22594&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8345632
  Stats: 6 lines in 1 file changed: 5 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/22594.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22594/head:pull/22594

PR: https://git.openjdk.org/jdk/pull/22594