The ornamental design of a candleholder, as shown and described.
FIG. 1 is a front perspective view of a candle holder in accordance with the present invention;
FIG. 2 is a right side elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a left side elevation view thereof;
FIG. 5 is a front elevation view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines showing on the lower base portion of the candle holder illustrate the portions of the candle holder that form no part of the claimed design. The broken lines showing silhouette of a candle in the drawing views represent environmental structure and form no part of the claimed design.