ConnectionMap::getConnection() should be const
ConnectionMap::getConnection() should be const

Change-Id: I607d8069107dac82ae66a93b3792fa0b53e60cb5
Reviewed-on: http://review.couchbase.org/c/kv_engine/+/134652
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Jim Walker <1cd02e31b43620d7c664e038ca42a060d61727b9@couchbase.com>

daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine