Fix : Floodfill infinite recursion due to same color (#4359)

Fix : Floodfill infinite recursion due to same color

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

@@ -39,6 +39,7 @@ public class FloodFill {
      * @param oldColor The old color which is to be replaced in the image
      */
     public static void floodFill(int[][] image, int x, int y, int newColor, int oldColor) {
+        if (newColor == oldColor) return;
         if (x < 0 || x >= image.length) return;
         if (y < 0 || y >= image[x].length) return;
         if (getPixel(image, x, y) != oldColor) return;