[CommCoreModule] Use CONNECTING instead of 0 in readyState initialization

Summary: Super minor fix, should've switched this over when we introduced the SocketStatus enum

Test Plan: Still builds

Reviewers: ashoat, def-au1t, palys-swm, varun, karol-bisztyga

Reviewed By: ashoat

Subscribers: Adrian, benschac

Differential Revision: https://phabricator.ashoat.com/D3154