Implement the Stage 1 BLIS-NG launcher update

[hakiatalov]

As the BLIS-NG Update Service,
Given that there is a new BLIS-NG.exe file in the upgrade artifact,
I want to perform update the launcher by replacing the old BLIS-NG.exe file in the BLIS directory.

After the BLIS-NG launcher is updated, continue to the Stage 2 update without the user having to interact with the system. For now, just provide a log output: "Continuing to Stage 2 update."

This can be accomplished via a shell script that handles replacing the BLIS-NG.exe file and restarting the launcher with a --resume flag, or it can be accomplished in place, without restarting the launcher. Implementation up to the developer.

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AC

1. Given an updated BLIS-NG.exe file in the BLIS upgrade artifact, When the update process begins, Then the BLIS-NG launcher is updated first.
2. Given an updated BLIS-NG.exe file in the BLIS upgrade artifact, When the launcher updated completes, Then the system begins the Stage 2 update without manual intervention.