The ornamental design for a container with elongatedbase, as shown and described.
FIG. 1 is a top, front, side perspective view of a container with elongated base showing my new design;
FIG. 2 is a side elevation thereof;
FIG. 3 is a side elevation from opposite side thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is a top, front, side perspective view thereof showing a cap separated from the container.
The broken lines, the areas within them, and the areas bounded by broken lines and solid lines depict portions of the glass container with elongated base that form no part of the claimed design.