bug fix needed for release/1.11.0

[Bruce Schuchardt]

The PR for GEODE-6661 introduced a problem in SSL communications that 
needs to be fixed.  It changed SSL handshakes to use a temporary buffer 
that's discarded when the handshake completes, but sometimes this buffer 
contains application data that must be retained.  This seems to be 
causing our Benchmark SSL test failures in CI.

I'm preparing a fix.  We can either revert the PR for GEODE-6661 on that 
branch or cherry-pick the correction when it's ready.