Fix checkstyle violations.

Author: Maryamh12

src/main/java/com/thealgorithms/backtracking/WordSearch.java

@@ -83,7 +83,7 @@ private boolean isValid(int x, int y) {
     //    }
 
     private boolean dfs(char[][] board, int x, int y, String word, int idx) {
-        if (idx == word.length()) return true;
+        if (idx == word.length()) { return true; }
 
         if (x < 0 || y < 0 || x >= board.length || y >= board[0].length || board[x][y] != word.charAt(idx)) {
             return false;