Predeclare spotless dependency on googleJavaFormat

[mcculls]

What Does This Do

Predeclare spotless dependency on googleJavaFormat so it downloads it once, rather than multiple modules racing to download it

Motivation

Avoids this intermittent error:

  Execution failed for task ':class-inject:spotlessJavaCheck' (registered by plugin 'java-common').
  > There were 4 lint error(s), they must be fixed or suppressed.
    src/glue/java/datadog/instrument/glue/DefineClassGlueGenerator.java:LINE_UNDEFINED google-java-format(java.lang.NoClassDefFoundError) com/google/common/collect/ImmutableSet$Builder (...)
    src/main/java/datadog/instrument/classinject/ClassInjector.java:LINE_UNDEFINED google-java-format(java.lang.NoClassDefFoundError) com/google/common/collect/ImmutableSet$Builder (...)
    src/main/java/datadog/instrument/classinject/package-info.java:LINE_UNDEFINED google-java-format(java.lang.NoClassDefFoundError) com/google/common/collect/ImmutableSet$Builder (...)
    src/test/java/datadog/instrument/glue/DefineClassGlueGeneratorTest.java:LINE_UNDEFINED google-java-format(java.lang.NoClassDefFoundError) com/google/common/collect/ImmutableSet$Builder (...)
    Resolve these lints or suppress with `suppressLintsFor

Additional Notes

Contributor Checklist

Jira ticket: [PROJ-IDENT]