Integration tests: Use zaptest.Logger based testing.TB

Thanks to this the logs:
  - are automatically printed if the test fails.
  - are in pretty consistent format.
  - are annotated by 'member' information of the cluster emitting them.

Side changes:
  - Set propert default got DefaultWarningApplyDuration (used to be '0')
  - Name the members based on their 'place' on the list (as opposed to
'random')

test.sh

@@ -110,7 +110,7 @@ function integration_extra {
 
 function integration_pass {
   local pkgs=${USERPKG:-"./integration/..."}
-  run_for_module "tests" go_test "${pkgs}" "parallel" : -timeout="${TIMEOUT:-15m}" "-v" "${COMMON_TEST_FLAGS[@]}" "${RUN_ARG[@]}" "$@" || return $?
+  run_for_module "tests" go_test "${pkgs}" "parallel" : -timeout="${TIMEOUT:-15m}" "${COMMON_TEST_FLAGS[@]}" "${RUN_ARG[@]}" "$@" || return $?
   integration_extra "$@"
 }