[mlir][linalg] Only compose PadTensorOps if no ExtractSliceOp is rank-reducing.

Do not compose pad tensor operations if the extract slice of the outer pad tensor operation is rank reducing. The inner extract slice op cannot be rank-reducing since it source type must match the desired type of the padding.

Depends On D115359

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D115428