[CI] Add blob unit tests GH action

Summary:
Resolves part of ENG-1789. This diff adds a GH action that runs blob service unit tests.
Mostly copy-paste of identity tests.

Test Plan: Workflow results: https://github.com/CommE2E/comm/actions/runs/5252979341/jobs/9489719902

Reviewers: atul, jon

Reviewed By: atul, jon

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D8188