issue with Travis deploy with gradle

[csantanapr]

failure: https://travis-ci.org/ibm-functions/runtime-nodejs/builds/276322251

FAILURE: Build failed with an exception.
* Where:
Build file '/home/travis/build/ibm-functions/runtime-nodejs/tests/build.gradle' line: 23
* What went wrong:
A problem occurred evaluating project ':tests'.
> Could not get unknown property 'sourceSets' for project ':whisktests' of type org.gradle.api.Project.
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
* Get more help at https://help.gradle.org
BUILD FAILED in 6s