storage proxy: be more vocal about timeouts
storage proxy: be more vocal about timeouts

If a timeout happens, we should log it. Trace level is really
not adequate for this.

Signed-off-by: Glauber Costa <f8b79557d19b40666ebe336545a0b6178af65685@scylladb.com>

raphaelsc/scylla,kjniemi/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,duarten/scylla,duarten/scylla,avikivity/scylla,duarten/scylla,raphaelsc/scylla,scylladb/scylla,raphaelsc/scylla,scylladb/scylla,kjniemi/scylla,avikivity/scylla,kjniemi/scylla