[CI] Bump QEMU version

Summary:
We have troubles running tests on qemu because of slugginess, so updating to a more recent version can't hurt.

Depends on D14815.

Test Plan: Run the ARM and AARCH64 CI builds.

Reviewers: #bitcoin_abc, PiRK

Reviewed By: #bitcoin_abc, PiRK

Differential Revision: https://reviews.bitcoinabc.org/D14813