The ornamental design for the bathroom tissue holder, as shown and described.
FIG. 1 is a perspective view of a bathroom tissue holder showing my new design;
FIG. 2 is a front side elevational view thereof;
FIG. 3 is a back side elevational view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a right side elevational view thereof, the left side being a mirror image; and,
FIG. 6 is a bottom plan view thereof.
The broken-line disclosure of the fragmentary rod element and toilet roll are shown for illustrative purposes only and form no part of the claimed design.