Getting error "exec: 'gotestsum': executable file not found in $PATH"

I'm experimenting with unit tests in my terraform step, but when I execute Runiac it reports that a test has been found but after the step runs and it tries to execute the test I'm getting the error "exec: 'gotestsum': executable file not found in $PATH".

Here's the log before the error:

Running command: gotestsum --format standard-verbose --junitfile /output/junit/azure-hello-world-default-namespace-primary-centralus.xml --raw-command -- test2json -p azure-hello-world-default-namespace-primary-centralus ./tests.test -test.v.
EnvVars: [TF_VAR_runiac_step, TF_VAR_runiac_region_group, TF_VAR_runiac_target_account_id, TF_VAR_runiac_project, TF_VAR_runiac_region_deploy_type, TF_VAR_runiac_account_id, TF_VAR_runiac_region, TF_VAR_runiac_track, TF_VAR_runiac_primary_region, TF_VAR_runiac_namespace, TF_VAR_runiac_deployment_ring, TF_VAR_runiac_app_version, TF_VAR_runiac_environment]

Start by locating the Runiac code that assembles the logged gotestsum command and configures the test step environment. Reproduce the Terraform-step invocation, then trace how the executable is resolved from PATH; done means the reported test command runs successfully or produces a clear configuration error.