The ornamental design for a tete-a-tete chair, substantially as shown and described.
FIG. 1 is a front perspective view of a tete-a-tete chair in accordance with the present invention;
FIG. 2 is a rear perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top view thereof; and,
FIG. 8 is a bottom view thereof.
The broken lines in the figures are for the purpose of illustrating portions of the tete-a-tete chair, which form no part of the claimed design. Any shading or hatching are not features of the design and are merely utilized to illustrate surface contours of the design in the drawings.