OOB generation broken

[esune]

Generating OOB proof-request payloads broke, likely as a consecuence of this PR to enforce using a local DID.

The error being thrown is the following:

controller-1     | http://aca-py:8077 "GET /wallet/did/public HTTP/1.1" 200 16
controller-1     | {"status_code": 500, "process_time": 0.10548281669616699, "event": "failed to process a request", "logger": "api.main", "level": "info", "timestamp": "2024-03-20T23:42:08.324265Z"}
controller-1     | {"event": "Traceback (most recent call last):\n  File \"pydantic/main.py\", line 522, in pydantic.main.BaseModel.parse_obj\nTypeError: 'NoneType' object is not iterable\n\nThe above exception was the direct cause of the following exception:\n\nTraceback (most recent call last):\n  File \"/app/api/main.py\", line 90, in logging_middleware\n    response: Response = await call_next(request)\n                         ^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/usr/local/lib/python3.11/site-packages/starlette/middleware/base.py\", line 84, in call_next\n    raise app_exc\n  File \"/usr/local/lib/python3.11/site-packages/starlette/middleware/base.py\", line 70, in coro\n    await self.app(scope, receive_or_disconnect, send_no_error)\n  File \"/usr/local/lib/python3.11/site-packages/starlette/middleware/cors.py\", line 83, in __call__\n    await self.app(scope, receive, send)\n  File \"/usr/local/lib/python3.11/site-packages/starlette/middleware/exceptions.py\", line 79, in __call__\n    raise exc\n  File \"/usr/local/lib/python3.11/site-packages/starlette/middleware/exceptions.py\", line 68, in __call__\n    await self.app(scope, receive, sender)\n  File \"/usr/local/lib/python3.11/site-packages/fastapi/middleware/asyncexitstack.py\", line 21, in __call__\n    raise e\n  File \"/usr/local/lib/python3.11/site-packages/fastapi/middleware/asyncexitstack.py\", line 18, in __call__\n    await self.app(scope, receive, send)\n  File \"/usr/local/lib/python3.11/site-packages/starlette/routing.py\", line 718, in __call__\n    await route.handle(scope, receive, send)\n  File \"/usr/local/lib/python3.11/site-packages/starlette/routing.py\", line 276, in handle\n    await self.app(scope, receive, send)\n  File \"/usr/local/lib/python3.11/site-packages/starlette/routing.py\", line 66, in app\n    response = await func(request)\n               ^^^^^^^^^^^^^^^^^^^\n  File \"/usr/local/lib/python3.11/site-packages/fastapi/routing.py\", line 237, in app\n    raw_response = await run_endpoint_function(\n                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/usr/local/lib/python3.11/site-packages/fastapi/routing.py\", line 163, in run_endpoint_function\n    return await dependant.call(**values)\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/app/api/routers/oidc.py\", line 138, in get_authorize\n    wallet_did = client.get_wallet_did(public=True)\n                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/app/api/core/acapy/client.py\", line 124, in get_wallet_did\n    did = WalletDid.parse_obj(resp_payload)\n          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"pydantic/main.py\", line 525, in pydantic.main.BaseModel.parse_obj\npydantic.error_wrappers.ValidationError: 1 validation error for WalletDid\n__root__\n  WalletDid expected dict not NoneType (type=type_error)\n", "logger": "api.main", "level": "error", "timestamp": "2024-03-20T23:42:08.351949Z"}