Off by one error in example game 07_snake.py
**Describe the bug**
In the snake example game, the player dies when they touch one pixel from the top of the area, instead of the top of the area.

This line:
`        if head.x < 0 or head.y <= HEIGHT_SCORE or head.x >= WIDTH or head.y >= HEIGHT:`
Should be changed to
`        if head.x < 0 or head.y < HEIGHT_SCORE or head.x >= WIDTH or head.y >= HEIGHT:`
(or use `head.y <= HEIGHT_SCORE - 1`)
**Expected behavior**
If HEIGHT_SCORE is 6, the player should still be alive when occupying a point with `y == 6` (since score text area will only occupy space from Y0 to Y5)
