java.lang.IllegalArgumentException: Null value not allowed as an environment variable: TESTFLIGHT_CONFIG_URL
	at hudson.EnvVars.put(EnvVars.java:162)
	at hudson.EnvVars.put(EnvVars.java:64)
	at java.util.AbstractMap.putAll(AbstractMap.java:256)
	at java.util.TreeMap.putAll(TreeMap.java:304)
	at testflight.TestflightRecorder$EnvAction.buildEnvVars(TestflightRecorder.java:366)
	at hudson.model.AbstractBuild.getEnvironment(AbstractBuild.java:867)
	at hudson.tasks.Mailer.perform(Mailer.java:112)
	at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:19)
	at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:717)
	at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:692)
	at hudson.model.Build$BuildExecution.post2(Build.java:183)
	at hudson.model.AbstractBuild$AbstractBuildExecution.post(AbstractBuild.java:639)
	at hudson.model.Run.execute(Run.java:1527)
	at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
	at hudson.model.ResourceController.execute(ResourceController.java:88)
	at hudson.model.Executor.run(Executor.java:236)