Create and persist an authorized session object for MfgInspector.

[copybara-service]

Create and persist an authorized session object for MfgInspector.

AuthorizedSession allows us to persist connections across multiple requests to the same host. This means the manufacturing inspector client will re-use existing connections from the pool which reduces overhead and latency. Requests are processed faster and sessions automatically handle keep-alive connections. Additionally, session related data (e.g. auth) is persisted which improves performance. Given our partial uploader implementation, this will be beneficial to both client and server.

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