Building UE4Game fails during the build phase while packaging on Linux

This is happening only for Blueprint template projects. After I hit the issue on the BP project, I went back and tried a Code template project as well. I was NOT able to reproduce this with a Code template project.

Various libUE4-<foo>.a files are generating "File format not recognized" during the build phase.

For example:

UATHelper: Packaging (Linux): UnrealBuildTool: /usr/bin/ar: /home/michael/Desktop/GitHub_Builds/Release-4.16/3447352/Engine/Plugins/Online/OnlineSubsystemNull/Binaries/Linux/libUE4-OnlineSubsystemNull.a: File format not recognized

Repro:

1. Download the following git hub build https://github.com/EpicGames/UnrealEngine/archive/cbaba4b5268ddbf6fd4cba434c0ec2e076c235ee.zip
2. Unzip the build.
3. In the root folder, open a terminal and run the command:

   ./Engine/Build/BatchFiles/Linux/Setup.sh

4. Once that completes, run the command:

   ./Engine/Build/BatchFiles/Linux/GenerateProjectFiles.sh

5. After that, run the command:

   make all ARGS=-clean && make all

6. Open the editor via:

   ./Engine/Binaries/Linux/UE4Editor

7. Create a Blueprint first person project on Linux
8. Package a development build for Linux

Result:
UE4Game fails to be build due to file format no recognized errors for various .a files