Fix coveralls.

gradle/coveralls.gradle

   additionalSourceDirs = files(subprojects.sourceSets.main.allSource.srcDirs)
   sourceDirectories = files(subprojects.sourceSets.main.allSource.srcDirs)
   classDirectories = files(subprojects.sourceSets.main.output)
-  executionData = files(subprojects.jacocoTestReport.executionData)
+  executionData = files(subprojects.jacocoTestReport.executionData).filter { it.exists() }
 
   reports {
     html.enabled = true
     xml.enabled = true
   }
-
-  doFirst {
-    executionData = files(executionData.findAll { it.exists() })
-  }
 }
 
 coveralls {