MB-42977: Cluster_testapp: Enable stderr for messages >= error

Change the logging config for cluster_testapp to print error and above
log messages to stderr. This aids in debugging any issues which occur
when a node fails to startup as those errors will be printed to stderr
(in addition to log file).

Change-Id: I14c25350318cf707bd7f15bdf3dbc8ae5b262db2
Reviewed-on: http://review.couchbase.org/c/kv_engine/+/141141
Tested-by: Build Bot <[email protected]>
Reviewed-by: Trond Norbye <[email protected]>

Author: daverigby

cluster_framework/node.cc

@@ -88,8 +88,8 @@ NodeImpl::NodeImpl(std::string directory, std::string id)
                 {"default", {{"slow", 500}}},
                 {"COMPACT_DB", {{"slow", "5 m"}}}}},
               {"logger",
-               {{"unit_test", true},
-                {"console", false},
+               {{"unit_test", false},
+                {"console", true},
                 {"filename", log_filename}}},
               {"breakpad",
                {{"enabled", true},

logger/spdlogger.cc

@@ -143,7 +143,7 @@ std::optional<std::string> cb::logger::initialize(
             if (logger_settings.unit_test) {
                 stderrsink->set_level(spdlog::level::trace);
             } else {
-                stderrsink->set_level(spdlog::level::warn);
+                stderrsink->set_level(spdlog::level::err);
             }
             sink->add_sink(stderrsink);
         }