testing/xmrig-proxy: upgrade to 5.4.0

Ref https://github.com/xmrig/xmrig-proxy/releases/tag/v5.4.0
7 jobs for !2268 with xmrig-proxy in 2 minutes and 34 seconds (queued for 1 second)
detached
Status Name Job ID Coverage
  Lint
passed lint #24712
docker-alpine x86_64

00:00:32

 
  Build
passed build-aarch64 #24717
docker-alpine ci-build aarch64

00:00:47

passed build-armv7 #24718
docker-alpine ci-build armv7

00:02:01

passed build-ppc64le #24716
docker-alpine ci-build ppc64le

00:00:49

passed build-s390x #24715
docker-alpine ci-build s390x

00:00:27

passed build-x86 #24714
docker-alpine ci-build x86

00:00:33

passed build-x86_64 #24713
docker-alpine ci-build x86_64

00:00:34