[docs] fix a typo Features.rst (#5463)

fix a typo in docs/Features.rst

docs/Features.rst

@@ -71,7 +71,7 @@ Optimization in Network Communication
 -------------------------------------
 
 It only needs to use some collective communication algorithms, like "All reduce", "All gather" and "Reduce scatter", in distributed learning of LightGBM.
-LightGBM implements state-of-art algorithms\ `[9] <#references>`__.
+LightGBM implements state-of-the-art algorithms\ `[9] <#references>`__.
 These collective communication algorithms can provide much better performance than point-to-point communication.
 
 .. _Optimization in Parallel Learning: