Update dataflow.properties to use 0.4.0 version instead of 0.4.0-incubating

[jbonofre]

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[jbonofre]

R: @dhalperi

[dhalperi]

LGTM, merged. Thanks jb!

[asfbot]

Refer to this link for build results (access rights to CI server needed):
https://builds.apache.org/job/beam_PreCommit_Java_MavenInstall/6316/

Build result: FAILURE

[...truncated 8554 lines...] at hudson.remoting.UserRequest.perform(UserRequest.java:50) at hudson.remoting.Request$2.run(Request.java:332) at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:68) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745)Caused by: org.apache.maven.plugin.MojoExecutionException: Archetype IT 'basic' failed: Execution failure: exit code = 1 at org.apache.maven.archetype.mojos.IntegrationTestMojo.execute(IntegrationTestMojo.java:269) at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208) ... 31 more2016-12-29T06:06:31.863 [ERROR] 2016-12-29T06:06:31.864 [ERROR] Re-run Maven using the -X switch to enable full debug logging.2016-12-29T06:06:31.864 [ERROR] 2016-12-29T06:06:31.864 [ERROR] For more information about the errors and possible solutions, please read the following articles:2016-12-29T06:06:31.864 [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException2016-12-29T06:06:31.864 [ERROR] 2016-12-29T06:06:31.864 [ERROR] After correcting the problems, you can resume the build with the command2016-12-29T06:06:31.864 [ERROR] mvn -rf :beam-sdks-java-maven-archetypes-starterchannel stoppedSetting status of 2e63133 to FAILURE with url https://builds.apache.org/job/beam_PreCommit_Java_MavenInstall/6316/ and message: 'Build finished. 'Using context: Jenkins: Maven clean install
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