WebClient's paginated response iterator does not work for admin.conversations.search API

[seratch]

Usually, next_cursor in an API response exists under response_metadata property. However, only admin.conversations.search API method's response has it at the top level: https://github.com/slackapi/java-slack-sdk/blob/main/slack-api-client/src/main/java/com/slack/api/methods/response/admin/conversations/AdminConversationsSearchResponse.java#L19

Due to this inconsistency, this part in this Python SDK does not work for the API. https://github.com/slackapi/python-slack-sdk/blob/v3.7.0/slack_sdk/web/slack_response.py#L141-L145 We can improve the internals of the class to support the API too.

• TODOs
  • Add unit tests to reproduce the pattern
  • Change the logic

Category (place an x in each of the [ ])

• slack_sdk.web.WebClient (sync/async) (Web API client)
• slack_sdk.webhook.WebhookClient (sync/async) (Incoming Webhook, response_url sender)
• slack_sdk.models (UI component builders)
• slack_sdk.oauth (OAuth Flow Utilities)
• slack_sdk.socket_mode (Socket Mode client)
• slack_sdk.audit_logs (Audit Logs API client)
• slack_sdk.scim (SCIM API client)
• slack_sdk.rtm (RTM client)
• slack_sdk.signature (Request Signature Verifier)

Requirements

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