libwebp: fix sha256 checksum (#15639)
libwebp: fix sha256 checksum (#15639)


LLNL/spack,iulian787/spack,LLNL/spack,iulian787/spack,iulian787/spack,iulian787/spack,LLNL/spack,LLNL/spack,iulian787/spack,LLNL/spack