testing/apulse: fix build with musl 1.2.5
Patch backported from: https://github.com/i-rinat/apulse/commit/d0c4ba7e561953a54b91ead87a3ff6c9c90efcee
Patch backported from: https://github.com/i-rinat/apulse/commit/d0c4ba7e561953a54b91ead87a3ff6c9c90efcee