MISC: Fix overusage of the CPU

Use the `sleep` function instead of `yield` to really release the CPU.

inc/lektor/config.def

@@ -17,7 +17,7 @@ section("repo")
 value("obfuscate",      "1")
 value("module",         "repo")
 value("name",           "Kurisu")
-value("workers_count",  "5")
+value("workers_count",  "2")
 value("url",            "https://kurisu.iiens.net")
 value("json",           "https://kurisu.iiens.net/api")
 value("id_json",        "https://kurisu.iiens.net/api?id=%ld")

src/module/worker.c

@@ -29,7 +29,7 @@ __worker_thread(void *__pool)
             break;
         } else {
             assert(!pthread_mutex_unlock((pthread_mutex_t *) &pool->lock));
-            sched_yield();
+            sleep(1);
             continue;
         }