fix a typo

Author: Qinghao Shi

Tutorials_UsingAPIs/Flow-Control-Active-Polling-Button/main.cpp

@@ -10,7 +10,7 @@ int main()
     while (1) {
         if (BUTTON_PRESS == button) {
             led = !led;
-            ThisThread::sleep_for(1000)
+            ThisThread::sleep_for(1000);
         }
     }
 }

Tutorials_UsingAPIs/Flow-Control-Ticker/main.cpp

@@ -17,6 +17,6 @@ int main()
     // spin in a main loop. flipper will interrupt it to call flip
     while (1) {
         led1 = !led1;
-        ThisThread::sleep_for((200);
+        ThisThread::sleep_for(200);
     }
 }