tests: use the test helpers in more places

This is mostly cosmetic. It makes those test binaries support SYSTEMD_LOG_*
environment variables.

src/libsystemd-network/test-lldp.c

@@ -15,6 +15,7 @@
 #include "lldp-network.h"
 #include "macro.h"
 #include "string-util.h"
+#include "tests.h"
 
 #define TEST_LLDP_PORT "em1"
 #define TEST_LLDP_TYPE_SYSTEM_NAME "systemd-lldp"
@@ -365,7 +366,7 @@ static void test_multiple_neighbors_sorted(sd_event *e) {
 int main(int argc, char *argv[]) {
         _cleanup_(sd_event_unrefp) sd_event *e = NULL;
 
-        log_set_max_level(LOG_DEBUG);
+        test_setup_logging(LOG_DEBUG);
 
         /* LLDP reception tests */
         assert_se(sd_event_new(&e) == 0);