Update secure session binary flag defaults
Update secure session binary flag defaults

This commit updates the defaults for the secure session test binary
to make it easier to test interoperability with the reference server,
now that it responds to HTTP requests.

PiperOrigin-RevId: 397784611
Change-Id: I15c436be7441bd68605e0d3933857c4ba70eafae

GoogleCloudPlatform/stet