Clean up package.json and update libraries

[t-hamano]

This PR updates npm libraries and removes unnecessary libraries.

Deleted libraries

The following libraries are dependencies of @wordpress/scripts, so they do not need to be installed separately.

• @wordpress/eslint-plugin
• @wordpress/browserslist-config
• @wordpress/stylelint-config
• @wordpress/prettier-config

Results of npm ls

$ npm ls @wordpress/eslint-plugin
create-block-theme@2.7.0 /home/t-hamano/projects/_core-dev/create-block-theme
├── @wordpress/eslint-plugin@21.0.0
└─┬ @wordpress/scripts@29.0.0
  └── @wordpress/eslint-plugin@21.0.0 deduped

$ npm ls @wordpress/browserslist-config
create-block-theme@2.7.0 /home/t-hamano/projects/_core-dev/create-block-theme
├── @wordpress/browserslist-config@6.7.0
├─┬ @wordpress/eslint-plugin@21.0.0
│ └─┬ @wordpress/babel-preset-default@8.7.0
│   └── @wordpress/browserslist-config@6.7.0 deduped
└─┬ @wordpress/scripts@29.0.0
  └── @wordpress/browserslist-config@6.7.0 deduped

$ npm ls @wordpress/stylelint-config
create-block-theme@2.7.0 /home/t-hamano/projects/_core-dev/create-block-theme
├─┬ @wordpress/scripts@29.0.0
│ └── @wordpress/stylelint-config@22.7.0 deduped
└── @wordpress/stylelint-config@22.7.0

$ npm ls @wordpress/prettier-config
create-block-theme@2.7.0 /home/t-hamano/projects/_core-dev/create-block-theme
├─┬ @wordpress/eslint-plugin@21.0.0
│ └── @wordpress/prettier-config@4.7.0 deduped
├── @wordpress/prettier-config@4.7.0
└─┬ @wordpress/scripts@29.0.0
  └── @wordpress/prettier-config@4.7.0 deduped

[pbking]

LGTM