Corrected the positioning of Box-drawing link in mazy-mice description

Removed the Box-drawing reference link from the code block area to the bottom of the document under the "Maze generation" section. This change was proposed to enhance the readability of the document and provide the link at a more appropriate location.

Author: Jegors Čemisovs

exercises/mazy-mice/description.md

@@ -52,8 +52,6 @@ The rectangular maze 6x18 cells
     └───┴───────┴───────┴─────┴─────┴───┘
 ```
 
-[Box-drawing]: https://en.wikipedia.org/wiki/Box-drawing_character
-
 ## Hints
 
 ### Maze generation
@@ -76,3 +74,4 @@ You can use any algorithm to generate a perfect maze. The [recursive backtracker
 |     ⇨     | rightwards white arrow                |  U+21E8 |
 
 [recursive-backtracker]: https://en.wikipedia.org/wiki/Maze_generation_algorithm
+[Box-drawing]: https://en.wikipedia.org/wiki/Box-drawing_character