Enable streaming of build logs

[pditommaso]

trafficstars

The build logs reported in the build controller are only accessible once the logs have been uploaded on the build completion.

However, it should be possible to fetch the K8s pod output stream to stream the log while the build is running.

The goal of this issue is to enable this capability

[munishchouhan]

@pditommaso so to make it more clear

1. Stream logs from k8s pod to S3 while build is in process
2. then build log spi will automatically get the current log

Is this what is required?

[pditommaso]

Nope, stream the k8s pod logs to the http client running the request