Build smoke-test-fake-backend Docker image for arm64 architecture

[jaydeluca]

Resolves #14358

Tested with my fork

Pulled locally and verified manifest for both architectures. I upgraded the base container to one with multi-architecture support, and updated the java version in the process because i hit some snags with the build using java 11.

I was a little hesitant to also touch the windows image, but I felt it made sense that if I upgraded the java version on one that I did it on both.

➜ ~ docker manifest inspect ghcr.io/jaydeluca/opentelemetry-java-instrumentation/smoke-test-fake-backend:20250807.16792023875 { "schemaVersion": 2, "mediaType": "application/vnd.docker.distribution.manifest.list.v2+json", "manifests": [ { "mediaType": "application/vnd.docker.distribution.manifest.v2+json", "size": 1567, "digest": "sha256:a234aaf90061c5977f98773a37f36191b9d728728ab4d4129f37be8c03f756ca", "platform": { "architecture": "amd64", "os": "linux" } }, { "mediaType": "application/vnd.docker.distribution.manifest.v2+json", "size": 1567, "digest": "sha256:d0dcadf7a63ce3bc202748cd0c60c011b01a3bcdaef047b94fc1ff1807ef87fc", "platform": { "architecture": "arm64", "os": "linux" } } ] }