Removing scp from ou results in failure in pipeline run

1. I have an OU directory aws-deployment-framework-bootstrap/adf-bootstrap/deployment with scp.json.
2. I need to try some things so I remove the scp, moving it to ../../deployment-scp.json.
3. I assume that scp from root (aws-deployment-framework-bootstrap/adf-bootstrap/scp.json) will kick in like in other OUs.
4. Instead I get an error when running pipeline:
```

[Container] 2020/03/23 09:21:07 Running command python adf-build/main.py
--
139 | 2020-03-23 09:21:07,510 \| INFO \| __main__ \| ADF Version 3.0.4 \| (main.py:235)
140 | 2020-03-23 09:21:07,510 \| INFO \| __main__ \| ADF Log Level is INFO \| (main.py:236)
141 | 2020-03-23 09:21:08,329 \| INFO \| organization_policy \| Determining if Organization Policy changes are required. (Tagging or Service Controls) \| (organization_policy.py:97)
142 | 2020-03-23 09:21:18,815 \| INFO \| organizations \| SERVICE_CONTROL_POLICY are currently enabled within the Organization \| (organizations.py:49)
143 | Traceback (most recent call last):
144 | File "adf-build/main.py", line 348, in
145 | main()
146 | File "adf-build/main.py", line 251, in main
147 | policies.apply(organizations, parameter_store, config.config)
148 | File "/codebuild/output/src516924998/src/adf-build/organization_policy.py", line 119, in apply
149 | organization_mapping, path, organizations, _type)
150 | File "/codebuild/output/src516924998/src/adf-build/organization_policy.py", line 84, in clean_and_remove_policy_attachment
151 | organizations.detach_policy(policy_id, organization_mapping[path])
152 | File "/codebuild/output/src516924998/src/adf-build/shared/python/organizations.py", line 125, in detach_policy
153 | TargetId=target_id
154 | File "/root/.pyenv/versions/3.7.6/lib/python3.7/site-packages/botocore/client.py", line 316, in _api_call
155 | return self._make_api_call(operation_name, kwargs)
156 | File "/root/.pyenv/versions/3.7.6/lib/python3.7/site-packages/botocore/client.py", line 599, in _make_api_call
157 | api_params, operation_model, context=request_context)
158 | File "/root/.pyenv/versions/3.7.6/lib/python3.7/site-packages/botocore/client.py", line 647, in _convert_to_request_dict
159 | api_params, operation_model)
160 | File "/root/.pyenv/versions/3.7.6/lib/python3.7/site-packages/botocore/validate.py", line 297, in serialize_to_request
161 | raise ParamValidationError(report=report.generate_report())
162 | botocore.exceptions.ParamValidationError: Parameter validation failed:
163 | Invalid type for parameter PolicyId, value: [], type: , valid types:
```
Moving scp back to original place resolves the issue.

Start with adf-build/organization_policy.py, especially clean_and_remove_policy_attachment, then follow the detach_policy call in adf-build/shared/python/organizations.py. Reproduce the pipeline case where the OU-level scp.json is moved aside and confirm how the root policy is selected. Done means the pipeline handles that layout without passing an invalid policy identifier to AWS Organizations.

Written by the indexing model from the issue text.