[Mosaic] Support squeezing tiled memrefs to 1d shapes.
Previously, squeezing to a 1D memref failed w/ verification errors, as we would always use the old layout.
If we are squeezing from a source to a 1D shape, we need to modify the tile dimensions when we emit the result layout, as the removed dimensions should not be included in the new tiling.
PiperOrigin-RevId: 757887087
