JUnit Vintage:ITBulkConnectionTest
    ClassSource [className = 'com.google.cloud.spanner.connection.it.ITBulkConnectionTest', filePosition = null]
    => java.lang.NullPointerException: Property spanner.testenv.config.class needs to be set
       com.google.cloud.spanner.IntegrationTestEnv.initializeConfig(IntegrationTestEnv.java:67)
       com.google.cloud.spanner.IntegrationTestEnv.before(IntegrationTestEnv.java:76)
       org.junit.rules.ExternalResource$1.evaluate(ExternalResource.java:50)
       org.junit.rules.RunRules.evaluate(RunRules.java:20)
       org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
       org.junit.runners.ParentRunner.run(ParentRunner.java:413)
       org.junit.runner.JUnitCore.run(JUnitCore.java:137)
       org.junit.runner.JUnitCore.run(JUnitCore.java:115)
       org.junit.vintage.engine.execution.RunnerExecutor.execute(RunnerExecutor.java:42)
       org.junit.vintage.engine.VintageTestEngine.executeAllChildren(VintageTestEngine.java:80)