provide test logs as soon as they are available (#755)
provide test logs as soon as they are available (#755)

Currently if a test fails one has to wait until the Bazel invocation
completes to be able to see the test.log. This change makes it so that
test.logs are uploaded concurrently to the test invocation as soon as
a test fails/flakes.
bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration