The ornamental design for a testdevice comprising a pipette holder, as shown and described.
FIG. 1 is a top perspective view of a test device comprising a pipette holder;
FIG. 2 is a first end view thereof;
FIG. 3 is a second end view thereof;
FIG. 4 is a first side view thereof;
FIG. 5 is a second side view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a bottom view thereof; and,
FIG. 8 is a top perspective view thereof.
The broken lines in the figures depict portions of the test device comprising a pipette holder that form no part of the claimed design. The dot-dash broken lines depict the boundaries of the claims and form no part thereof.