Jessie's Museum Authority Building Fixes

GAME CHANGES

Fixes issues with the stoop staircases in front of the Museum Authority Building.

Walking onto the stoop of the building via the staircases wasn't possible. The player had to jump up the staircases to ingress, and any companions (or enemies) couldn't follow the Lone Wanderer onto the stoop.

Some rubble (and invisible collision box trickery) allow simply walking up the stairs.

RATIONALE

Trying to walk up stairs only to have to jump just takes me out of the game.