Update the installation script for pip

[kazuma-t]

$ pip install SudachiDict-core
Collecting SudachiDict-core
  Downloading SudachiDict-core-20221021.tar.gz (9.0 kB)
  Preparing metadata (setup.py) ... done
Requirement already satisfied: SudachiPy<0.7,>=0.5 in ./.pyenv/versions/3.11.1/lib/python3.11/site-packages (from SudachiDict-core) (0.6.6)
Installing collected packages: SudachiDict-core
  DEPRECATION: SudachiDict-core is being installed using the legacy 'setup.py install' method, because it does not have a 'pyproject.toml' and the 'wheel' package is not installed. pip 23.1 will enforce this behaviour change. A possible replacement is to enable the '--use-pep517' option. Discussion can be found at https://github.com/pypa/pip/issues/8559
  Running setup.py install for SudachiDict-core ... done
Successfully installed SudachiDict-core-20221021