Not Able to Access Default Variables

I'm not sure if I'm doing something wrong, but I can't seem to get Monkeyble to read my role's **default** variables.
Here's a simplified POC:

This **does** work:
```
---
monkeyble_scenarios:
validate_test_1:
name: Validate create gMSA
tasks_to_test:
- task: "Create a Group Managed Service Account (gMSA)."
mock:
config:
hpe.monkeyble.monkeyble_module:
consider_changed: true
result_dict:
object_guid: "00000000-0000-0000-0000-000000000000"
# test_input:
# - assert_equal:
# arg_name: identity
# expected: fake_identity

inputs:
app_id: fake_app_id
identity: fake_identity
mailing_list: fake_mailing_list
principals: fake_principal1,fake_principal2
```

This **does not** work (the difference being the `test_input`):

```
---
monkeyble_scenarios:
validate_test_1:
name: Validate create gMSA
tasks_to_test:
- task: "Create a Group Managed Service Account (gMSA)."
mock:
config:
hpe.monkeyble.monkeyble_module:
consider_changed: true
result_dict:
object_guid: "00000000-0000-0000-0000-000000000000"
test_input:
- assert_equal:
arg_name: identity
expected: fake_identity

inputs:
app_id: fake_app_id
identity: fake_identity
mailing_list: fake_mailing_list
principals: fake_principal1,fake_principal2
```

```
╰─± ANSIBLE_CONFIG="/tmp/ansible.cfg" ansible-playbook tests/playbooks/test_create_gmsa.yml -e @tests/monkeyble.yml -e monkeyble_scenario=validate_test_1
[WARNING]: No inventory was parsed, only implicit localhost is available
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match 'all'

PLAY [Verify the role.] **************************************************************************************************************************************************************************************************************
🐵 Starting Monkeyble callback 1.7.1
monkeyble_scenario: validate_test_1
Monkeyble scenario: Validate create gMSA

TASK [active_directory : Validating arguments against arg spec 'create_gmsa' - Creates a Group Managed Service Account (gMSA)] *******************************************************************************************************
ok: [localhost]

TASK [active_directory : Create a Group Managed Service Account (gMSA).] *************************************************************************************************************************************************************
[WARNING]: Callback dispatch 'v2_runner_on_start' failed for plugin 'ansible_collections.hpe.monkeyble.plugins.callback.monkeyble_callback': 'active_directory' is undefined

Callback dispatch 'v2_runner_on_start' failed for plugin 'ansible_collections.hpe.monkeyble.plugins.callback.monkeyble_callback'.

<<< caused by >>>

'active_directory' is undefined
Origin:

2 - name: Create a Group Managed Service Account (gMSA).
3 microsoft.ad.service_account:
4 allowed_to_retrieve_password: "{{ active_directory.gmsa.allowed_to_retrieve_password }}"
^ column 35

[ERROR]: Task failed: Action failed: The module interpreter '/usr/bin/pwsh' was not found.

Task failed: Action failed.
Origin:

1 ---
2 - name: Create a Group Managed Service Account (gMSA).
^ column 3

<<< caused by >>>

The module interpreter '/usr/bin/pwsh' was not found. Consider overriding the configured interpreter path for this host. See stdout/stderr for the returned output.

fatal: [localhost]: FAILED! => {"changed": false, "module_stderr": "/bin/sh: /usr/bin/pwsh: No such file or directory\n", "module_stdout": "", "msg": "The module interpreter '/usr/bin/pwsh' was not found.", "rc": 127}
```

The second one works if I tack on a `-e @defaults/main.yml`. `active_directory` is defined here. Keys aside, even having it defined as an empty dict results in the same error without omitting the `test_input` or tacking on the flag.

```
╰─± ANSIBLE_CONFIG="/tmp/ansible.cfg" ansible-playbook tests/playbooks/test_create_gmsa.yml -e @tests/monkeyble.yml -e monkeyble_scenario=validate_test_1 -e @defaults/main.yml
[WARNING]: No inventory was parsed, only implicit localhost is available
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match 'all'

PLAY [Verify the role.] **************************************************************************************************************************************************************************************************************
🐵 Starting Monkeyble callback 1.7.1
monkeyble_scenario: validate_test_1
Monkeyble scenario: Validate create gMSA

TASK [active_directory : Validating arguments against arg spec 'create_gmsa' - Creates a Group Managed Service Account (gMSA)] *******************************************************************************************************
ok: [localhost]

TASK [active_directory : Create a Group Managed Service Account (gMSA).] *************************************************************************************************************************************************************
🙈 Monkeyble test input passed ✔
{"monkeyble_passed_test": [{"test_name": "assert_equal", "tested_value": "fake_identity", "expected": "fake_identity"}], "monkeyble_failed_test": []}
🙉 Monkeyble mock module - Before: 'microsoft.ad.service_account' Now: 'hpe.monkeyble.monkeyble_module'
changed: [localhost]

PLAY RECAP ***************************************************************************************************************************************************************************************************************************
localhost : ok=2 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0

🐵 Monkeyble - ALL TESTS PASSED ✔ - scenario: Validate create gMSA
```

Reproduce the issue with tests/playbooks/test_create_gmsa.yml and tests/monkeyble.yml, comparing runs with and without defaults/main.yml. Start by reading the Monkeyble callback at ansible_collections.hpe.monkeyble.plugins.callback.monkeyble_callback and trace how test_input evaluates role variables; done means active_directory is available without the extra defaults file and the assertion passes.

Written by the indexing model from the issue text.