time: reduce chances of failures on the CI, by time_test.c.v; make the failure diagnostic easier

Author: spytheman

vlib/time/time_test.c.v

@@ -9,6 +9,15 @@ fn test_tm_gmtoff() {
 		C.time(&rawtime) // C.tm{}
 
 		info := C.localtime(&rawtime)
-		assert info.tm_gmtoff == time.now().unix() - time.utc().unix()
+		t1 := time.now()
+		t2 := time.utc()
+		dump(t1)
+		dump(t2)
+		dump(t1.nanosecond)
+		dump(t2.nanosecond)
+		diff := t1.unix() - t2.unix()
+		dump(diff)
+		dump(info.tm_gmtoff)
+		assert info.tm_gmtoff == diff
 	}
 }