Support custom Azure Blob Storage endpoint / endpoint suffix for sovereign clouds

Quickwit currently supports Azure Blob Storage using the following configuration:

storage:
  azure:
    account: <storage-account-name>
    access_key: <storage-account-access-key>

However, there does not appear to be a way to configure a custom Azure Blob Storage endpoint.

This makes it difficult to use Quickwit with Azure environments that do not use the default public Azure endpoints, such as Azure Government, Azure China, Azure Stack, or other Azure deployments with custom endpoints.

I'd like Quickwit to support configuring a custom Azure Blob Storage endpoint so that it can connect to Azure Blob Storage deployments outside the public Azure cloud.

I haven't found an existing configuration option that allows overriding the Azure Blob Storage endpoint in Quickwit. At the moment, the only alternative appears to be modifying Quickwit's source code to add support for custom endpoints.

Azure Blob Storage endpoints vary across Azure cloud environments. For example:

Public Azure: https://.blob.core.windows.net
Azure Government: https://.blob.core.usgovcloudapi.net
Azure China: https://.blob.core.chinacloudapi.cn

Supporting configurable Azure Blob Storage endpoints would enable Quickwit to work seamlessly across Azure sovereign clouds, Azure Stack, and other Azure deployments that expose Blob Storage through non-default endpoints.

Start by tracing the storage.azure configuration and the Azure Blob Storage client setup. Determine how a configurable endpoint or endpoint suffix should be represented, then verify that the listed public, Government, China, and other non-default endpoint forms can be used without source changes.