Add module-info.java

[cowwoc]

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Is your feature request related to a problem? Please describe.
When I use this library as a dependency in my own library I get this compile-time warning:

[WARNING] *************************************************************************************************************************************************************
[WARNING] * Required filename-based automodules detected: [proto-google-common-protos-2.51.0.jar]. Please don't publish this project to a public artifact repository! *
[WARNING] *************************************************************************************************************************************************************

Describe the solution you'd like
Add module-info.java to this library.