test: add test / example of using rootpath on a run_binary directory output

[gregmagolan]

In support of a Bazel Slack question on location of run_binary out_dirs: https://bazelbuild.slack.com/archives/C04281DTLH0/p1717607601723849?thread_ts=1717158361.547679&cid=C04281DTLH0.

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Changes are visible to end-users: no

Test plan

• New test cases added

[aspect-workflows]

Test

5 test targets passed

Targets

//lib/tests/copy_to_directory_bin_action:test [k8-fastbuild] 83ms
//lib/tests/jq:check_stamped [k8-fastbuild]                  359ms
//lib/tests/run_binary:dir_a_rootpath_test [k8-fastbuild]    220ms
//lib/tests/run_binary:dir_test [k8-fastbuild]               58ms
//lib/tests/yq:check_stamped [k8-fastbuild]                  101ms

Total test execution time was 821ms. 211 tests (97.7%) were fully cached saving 43s.

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Test

e2e/copy_action

All tests were cache hits

1 test (100.0%) was fully cached saving 73ms.

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Test

e2e/copy_to_directory

All tests were cache hits

6 tests (100.0%) were fully cached saving 583ms.

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Test

e2e/coreutils

All tests were cache hits

4 tests (100.0%) were fully cached saving 423ms.

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Test

e2e/external_copy_to_directory

All tests were cache hits

1 test (100.0%) was fully cached saving 73ms.

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Test

e2e/smoke

All tests were cache hits

6 tests (100.0%) were fully cached saving 2s.

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Buildifier      Format      Gazelle