Fix Juggernaut Potion (Restrict Walking)

[ktksan]

The Juggernaut potion is supposed to restrict the Player's movements in exchange for damage resistance for 10 seconds.
Currently the potion does restrict jumping but the player is still free to walk around.

To fix: Either render the player completely immobile or reduce the walking speed to a very minimal amount (see Immobility potion).

To try the potions: Enable the Potions module and start the game in the JS or Core Gameplay game modes and then use 'give' command in the console to obtain the potions.