Small 2D and BRT fixes

[annshress]

Changes

• Add notify api running calls as soon as the flow runs start
• czi flow run uses async/await. Wait for prefect future results before sending it to async calls
• Remove subflow for small dm conversion flow
• Revert Completion/Failed to original success/error api calls on notify-api-completion
• Refactor BRT flow: ; Increase cluster size for BRT workflow to be able to handle large number of inputs.
• post workflow tasks uses .wait and .get_state to make sure the upstream tasks have completed (not necessarily reached a terminal state).

This PR doesn't introduce any:

• [x] Binary files
• [x] Temporary files, auto-generated files
• [x] Secret keys
• [x] Local debugging print statements
• [x] Unwanted comments (e.g: # Gets user from environment for code os.environ['user'] )

This PR contains valid:

• [ ] tests

[annshress]

Todo: Remove duplicate functions in utils.py for bf2raw_gen_zarr and zarr_build_multiscales.