Unclear error for export issues

[mikaelweave]

Describe the bug
When users are running the $export operation, a more clear error when the FHIR Server cannot access the backend storage would be immensely helpful for configuration issues. The below error is when then managed identity for FHIR does not have access to the storage account.

This is really hard to read and figure out the error. It would make more sense to parse this as an access issue from the blob backend and print a more readable error message.

{
    "resourceType": "OperationOutcome",
    "id": "56d845bc8a3372d7a3a03bdfe9930522",
    "meta": {
        "lastUpdated": "2022-10-31T19:47:24.9929489+00:00"
    },
    "issue": [
        {
            "severity": "error",
            "code": "processing",
            "diagnostics": "export operation failed for reason: This request is not authorized to perform this operation.\nRequestId:48f0f96b-401e-0006-6161-eda3e6000000\nTime:2022-10-31T19:45:16.4258654Z\r\nStatus: 403 (This request is not authorized to perform this operation.)\r\nErrorCode: AuthorizationFailure\r\n\r\nContent:\r\n<?xml version=\"1.0\" encoding=\"utf-8\"?><Error><Code>AuthorizationFailure</Code><Message>This request is not authorized to perform this operation.\nRequestId:48f0f96b-401e-0006-6161-eda3e6000000\nTime:2022-10-31T19:45:16.4258654Z</Message></Error>\r\n\r\nHeaders:\r\nServer: Microsoft-HTTPAPI/2.0\r\nx-ms-request-id: 48f0f96b-401e-0006-6161-eda3e6000000\r\nx-ms-client-request-id: 4c4a2c71-0d13-462a-91bb-82f1b3d97398\r\nx-ms-error-code: AuthorizationFailure\r\nDate: Mon, 31 Oct 2022 19:45:16 GMT\r\nContent-Length: 246\r\nContent-Type: application/xml"
        }
    ]
}

FHIR Version?
All

Data provider?
Both

To Reproduce
Steps to reproduce the behavior:

1. Setup export without giving the managed identity "Storage Blob Data Contributor"

AB#97934