Cherry pick an upstream patch to fix a memory leak.
Fixed in OpenWrt main branch in commit
2c2cea8864db ("package: update jsonfilter to latest HEAD 2026-03-12")
Link: e086664e6a
Link: https://github.com/openwrt/openwrt/pull/22440
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
(cherry picked from commit 77d54cca84ffbb7754d592712ee96b0fcbff0d92)