Fix google cloud keep alive settings

[mdedetrich]

So when trying to upload a file to google cloud storage I received the following error

org.apache.pekko.http.impl.engine.client.OutgoingConnectionBlueprint$UnexpectedConnectionClosureException: The http server closed the connection unexpectedly before delivering responses for 1 outstanding requests
    at org.apache.pekko.http.impl.engine.client.OutgoingConnectionBlueprint$.$anonfun$apply$7(OutgoingConnectionBlueprint.scala:135)
    at org.apache.pekko.http.impl.engine.client.OutgoingConnectionBlueprint$.$anonfun$apply$7$adapted(OutgoingConnectionBlueprint.scala:135)
    at org.apache.pekko.http.impl.util.One2OneBidiFlow$One2OneBidi$$anon$1$$anon$4.onUpstreamFinish(One2OneBidiFlow.scala:112)
    at org.apache.pekko.stream.impl.fusing.GraphInterpreter.processEvent(GraphInterpreter.scala:537)
    at org.apache.pekko.stream.impl.fusing.GraphInterpreter.execute(GraphInterpreter.scala:401)
    at org.apache.pekko.stream.impl.fusing.GraphInterpreterShell.runBatch(ActorGraphInterpreter.scala:662)
    at org.apache.pekko.stream.impl.fusing.ActorGraphInterpreter$SimpleBoundaryEvent.execute(ActorGraphInterpreter.scala:71)
    at org.apache.pekko.stream.impl.fusing.ActorGraphInterpreter$SimpleBoundaryEvent.execute$(ActorGraphInterpreter.scala:67)
    at org.apache.pekko.stream.impl.fusing.ActorGraphInterpreter$BatchingActorInputBoundary$OnComplete.execute(ActorGraphInterpreter.scala:103)
    at org.apache.pekko.stream.impl.fusing.GraphInterpreterShell.processEvent(ActorGraphInterpreter.scala:637)
    at org.apache.pekko.stream.impl.fusing.ActorGraphInterpreter.org$apache$pekko$stream$impl$fusing$ActorGraphInterpreter$$processEvent(ActorGraphInterpreter.scala:813)
    at org.apache.pekko.stream.impl.fusing.ActorGraphInterpreter$$anonfun$receive$1.applyOrElse(ActorGraphInterpreter.scala:831)
    at org.apache.pekko.actor.Actor.aroundReceive(Actor.scala:547)
    at org.apache.pekko.actor.Actor.aroundReceive$(Actor.scala:545)
    at org.apache.pekko.stream.impl.fusing.ActorGraphInterpreter.aroundReceive(ActorGraphInterpreter.scala:729)
    at org.apache.pekko.actor.ActorCell.receiveMessage(ActorCell.scala:590)
    at org.apache.pekko.actor.ActorCell.invoke(ActorCell.scala:557)
    at org.apache.pekko.dispatch.Mailbox.processMailbox(Mailbox.scala:272)
    at org.apache.pekko.dispatch.Mailbox.run(Mailbox.scala:233)
    at org.apache.pekko.dispatch.Mailbox.exec(Mailbox.scala:245)
    at java.util.concurrent.ForkJoinTask.doExec
    at java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec
    at java.util.concurrent.ForkJoinPool.scan
    at java.util.concurrent.ForkJoinPool.runWorker
    at java.util.concurrent.ForkJoinWorkerThread.run

I did some reading at googleapis/nodejs-storage#101 (comment) and https://pekko.apache.org/docs/pekko-http/current/configuration.html, my current theory is that we need to make sure that both the connection pool has its keep alive timeout set to infinity and any requests using the Connection: Keep Alive header explicitly

@raboof @jrudolph Would be good if you manage to look into this, I am not 100% sure that this will actually solve the underlying issue, its just based off of what I could find on the internet.

[mdedetrich]

Since we have added an extra keep alive header we know return 2 headers, but we still only check the first header for what we expect