Running tests for arm CI

[TingDaoK]

Issue #, if available:

• The arm build was not running tests as expected

Description of changes:

• Fix the CI to run tests properly for linux-musl-arm
• Fix reading the environment variable properly
• Tried to use codebuild arm host for the ARM, referring to https://docs.aws.amazon.com/codebuild/latest/userguide/action-runner.html. But, for armv7, we still need qemu and nothing really improves
• Also, looks like the log is missing somehow when we use codebuild, eg: https://github.com/awslabs/aws-crt-java/actions/runs/9457170557/job/26060185356
• Another finding worth to mention is multiarch/qemu-user-static does not support arm host properly, here is my attempt to use https://github.com/dbhi/qus for arm host, which works, but we suffer from the docker pull limits, and no needs as we are not using arm host now.

TODO:

• We should probably move the armv7 test separately as an integration test. Not running those for each commit pushed.
• github runner for ARM is coming soon, https://github.com/orgs/community/discussions/73040, which may also have the same issue that for armv7, we still need qemu to run, but may work better in term of missing log or the docker pull limits?

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[waahm7]

Great job 👍

[waahm7]

A comment about why we can't differentiate at runtime would be greatly appreciated.

[TingDaoK]

well, I also don't know... Just copy/paste from the comments in our CI before.