[BEAM-5875] Add missing dependency in test-utils module

[lgajowy]

This fixes nexmark suites failures.

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Post-Commit Tests Status (on master branch)

Lang	SDK	Apex	Dataflow	Flink	Gearpump	Samza	Spark
Go		---	---	---	---	---	---
Java
Python		---			---	---	---

[lgajowy]

I'm sorry - I should have tested this more thoroughly before. I successfully ran the smoke nexmark suites locally for direct and flink (local) runners using these instructions

[lgajowy]

@kennknowles could you take a look?

[kennknowles]

Cool. It would be nice to ensure this doesn't compile. I think we need Gradle's java-library plugin for that.

[kennknowles]

This is definitely needed based on a grep. So I'll merge this and assume mine is obsolete.

[lukecwik]

This should be compile scope

From

beam/buildSrc/src/main/groovy/org/apache/beam/gradle/BeamModulePlugin.groovy

Line 533 in f20e90a

// * compile - Required during compilation or runtime of the main source set.

:

    // By default, the shadow plugin is enabled to perform shading of commonly found dependencies.
    // Because of this it is important that dependencies are added to the correct configuration.
    // Dependencies should fall into one of these four configurations:
    //  * compile     - Required during compilation or runtime of the main source set.
    //                  This configuration represents all dependencies that much also be shaded away
    //                  otherwise the generated Maven pom will be missing this dependency.
    //  * shadow      - Required during compilation or runtime of the main source set.
    //                  Will become a runtime dependency of the generated Maven pom.
    //  * testCompile - Required during compilation or runtime of the test source set.
    //                  This must be shaded away in the shaded test jar.
    //  * shadowTest  - Required during compilation or runtime of the test source set.
    //                  TODO: Figure out whether this should be a test scope dependency
    //                  of the generated Maven pom.