Enable Darwin ARM64 binaries to be used in Bazel

[dbanetto]

Context

I've been trying to use container-structure-test via Bazel on a Darwin ARM64 machine without Rosetta and kept having the error:

==================== Test output for //:structure:
/private/var/tmp/_bazel_drb/90c1aedef04b4dc3f5392ec26da69ab7/sandbox/darwin-sandbox/321/execroot/_main/bazel-out/darwin_arm64-fastbuild/bin/structure.sh.runfiles/_main/structure.sh: line 24
: /private/var/tmp/_bazel_drb/90c1aedef04b4dc3f5392ec26da69ab7/sandbox/darwin-sandbox/321/execroot/_main/bazel-out/darwin_arm64-fastbuild/bin/structure.sh.runfiles/container_structure_test~~extension~structu
re_test_st_darwin_arm64/structure_test: Bad CPU type in executable
================================================================================

Double checking with:

❯ file bazel-out/darwin_arm64-fastbuild/bin/structure.sh.runfiles/container_structure_test\~\~extension\~structure_test_st_darwin_arm64/structure_test 
bazel-out/darwin_arm64-fastbuild/bin/structure.sh.runfiles/container_structure_test~~extension~structure_test_st_darwin_arm64/structure_test: Mach-O 64-bit executable x86_64

I validated that the toolchains were correct by adding --toolchain_resolution_debug='.*' to the bazel test execution

INFO: ToolchainResolution: Performing resolution of @@container_structure_test~//bazel:structure_test_toolchain_type for target platform @@local_config_platform//:host
      ToolchainResolution:   Toolchain @@container_structure_test~~extension~structure_test_st_darwin_amd64//:structure_test_toolchain is compatible with target plaform, searching for execution platforms:
      ToolchainResolution:     Incompatible execution platform @@local_config_platform//:host; mismatching values: x86_64
      ToolchainResolution:   Toolchain @@container_structure_test~~extension~structure_test_st_darwin_arm64//:structure_test_toolchain is compatible with target plaform, searching for execution platforms:
      ToolchainResolution:     Compatible execution platform @@local_config_platform//:host
      ToolchainResolution:   All execution platforms have been assigned a @@container_structure_test~//bazel:structure_test_toolchain_type toolchain, stopping
      ToolchainResolution: Recap of selected @@container_structure_test~//bazel:structure_test_toolchain_type toolchains for target platform @@local_config_platform//:host:
      ToolchainResolution:   Selected @@container_structure_test~~extension~structure_test_st_darwin_arm64//:structure_test_toolchain to run on execution platform @@local_config_platform//:host
INFO: ToolchainResolution: Target platform @@local_config_platform//:host: Selected execution platform @@local_config_platform//:host, type @@aspect_bazel_lib~//lib:jq_toolchain_type -> toolchain @@aspect_bazel_lib~~toolchain
s~jq_darwin_arm64//:jq_toolchain, type @@bazel_tools//tools/sh:toolchain_type -> toolchain @@bazel_tools~sh_configure_extension~local_config_sh//:local_sh, type @@container_structure_test~//bazel:structure_test_toolchain_type
 -> toolchain @@container_structure_test~~extension~structure_test_st_darwin_arm64//:structure_test_toolchain

After a lot of head scratching I came across this TODO comment, I have patched this out locally in my bazel workspace and it finally runs using the right architecture and the tests run & pass.

❯ file bazel-out/darwin_arm64-fastbuild/bin/structure.sh.runfiles/container_structure_test\~\~extension\~structure_test_st_darwin_arm64/structure_test 
bazel-out/darwin_arm64-fastbuild/bin/structure.sh.runfiles/container_structure_test~~extension~structure_test_st_darwin_arm64/structure_test: Mach-O 64-bit executable arm64

Side-note

If this patch is accepted and a new release tag is published: Can the Bazel Registry version also be bumped as well 🙏?

[dbanetto]

Hey @loosebazooka, Sorry to poke but is there anything blocking for this PR to be merged?