Fix validation to handle double respawn edge case

The harness incorrectly validates the situtation where both bots are on the respawn point.
(This situation can happen when the bots respawn on consecutive turns.)

This is what it can look like from a bot's prespective. 
```
Input                Output
###################  ###################
#........#........#  #........#........#
#*##.###.#.###.##*#  #*##.###.#.###.##*#
#.##.###.#.###.##.#  #.##.###.#.###.##.#
#.................#  #.................#
#.##.#.#####.#.##.#  #.##.#.#####.#.##.#
#....#...#...#....#  #....#...#...#....#
####.###.#.###.####  ####.###.#.###.####
####.#.......#.####  ####.#.......#.####
####.#.## ##.#.####  ####.#.## ##.#.####
    ...# B #...          ...# B #...    
####.#.## ##.#.####  ####.#.##A##.#.####
####.#.......#.####  ####.#.......#.####
####.#.#####.#.####  ####.#.#####.#.####
#........#........#  #........#........#
#.##.###.#.###.##.#  #.##.###.#.###.##.#
#*.#...........#.*#  #*.#...........#.*#
##.#.#.#####.#.#.##  ##.#.#.#####.#.#.##
#....#...#...#....#  #....#...#...#....#
#.######.#.######.#  #.######.#.######.#
#.................#  #.................#
###################  ###################
```
Currenlty the harness regards the only two valid moves as invalid.
This pull request fixes that.