The ornamental design for a toiletwatersupplylinefilter, as shown and described.
FIG. 1 is a front elevation view of a toilet water supply line filter showing my new design, each of the opposite side, the left side, and the right side being a mirror image of the shown;
FIG. 2 is a top plan view thereof;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is an isometric view thereof; and,
FIG. 5 is an in-use view thereof.
The broken lines in FIG. 5 of the drawings depict a toilet with a water supply line as environmental subject matter only and form no part of the claimed design.