testing/xmrig: upgrade to 5.6.0

Ref https://github.com/xmrig/xmrig/releases
7 jobs for !4133 with xmrig in 2 minutes and 13 seconds
detached
Status Job ID Name Coverage
  Lint
passed #50638
docker-alpine x86_64
lint

00:00:38

 
  Build
passed #50643
docker-alpine ci-build aarch64
build-aarch64

00:00:26

passed #50644
docker-alpine ci-build armv7
build-armv7

00:01:33

passed #50642
docker-alpine ci-build ppc64le
build-ppc64le

00:00:52

passed #50641
docker-alpine ci-build s390x
build-s390x

00:00:26

passed #50640
docker-alpine ci-build x86
build-x86

00:01:17

passed #50639
docker-alpine ci-build x86_64
build-x86_64

00:01:09