fix formatting

Author: pgs

README.md

@@ -45,7 +45,7 @@ A poker hand consists of 5 cards dealt from the deck. Poker hands are ranked by
 Sample input:
 
 | Black          | White          |
-|:---------------|:--------------:|
+|:--------------:|:--------------:|
 | 2H 3D 5S 9C KD | 2C 3H 4S 8C AH |
 | 2H 4S 4C 2D 4H | 2S 8S AS QS 3S |
 | 2H 3D 5S 9C KD | 2C 3H 4S 8C KH |