Replace noinspection instruction with proper @SuppressWarnings annotation

`//noinspection unchecked` suppresses unchecked cast warning only in the IDE. `@SuppressWarning` annotation properly suppresses both IDE and the compiler warnings.

Author: vkryl

example/java/org/drinkless/tdlib/Client.java

@@ -119,12 +119,12 @@ public void send(TdApi.Function query, ResultHandler resultHandler) {
      * @return request result.
      * @throws ExecutionException if query execution fails.
      */
+    @SuppressWarnings("unchecked")
     public static <T extends TdApi.Object> T execute(TdApi.Function<T> query) throws ExecutionException {
         TdApi.Object object = nativeClientExecute(query);
         if (object instanceof TdApi.Error) {
             throw new ExecutionException((TdApi.Error) object);
         }
-        //noinspection unchecked
         return (T) object;
     }