Issue:
You get the following error message with your Gradle build:
Caused by: java.io.IOException: Unable to delete directory '/bitrise/src/app/build' New files were found. This might happen because a process is still writing to the target directory.
Possible solutions:
Make sure you don't run the :clean Gradle task during the build. There is no need to do a clean build, because each Bitrise build starts with an empty virtual machine state.