session: Fix unchecked warning in SessionActor#handleMessage
session: Fix unchecked warning in SessionActor#handleMessage

Fixed by simplifying match ... case pattern match to a variable assignemnt
pattern match.

Signed-off-by: Sami Rosendahl <b33c757bb777642ab0d59c699f8d5782929a814f@reaktor.fi>

akisaarinen/ccf,akisaarinen/ccf