chore(package): restore changelog deploy scripts [ci skip]

Author: levithomason

Diff for: package.json

@@ -24,8 +24,10 @@
     "build:docs-toc": "doctoc ./.github/CONTRIBUTING.md --github --maxlevel 4",
     "build:docs-cname": "echo react.semantic-ui.com > docs/build/CNAME",
     "build:changelog": "github_changelog_generator --no-issues --no-unreleased --release-branch master --since-tag $(git describe --abbrev=0 --tags $(git rev-parse HEAD~400))",
+    "deploy:changelog": "git add CHANGELOG.md && git commit -m 'docs(changelog): update changelog [ci skip]' && git push",
     "predeploy:docs": "cross-env NODE_ENV=production yarn build:docs && yarn build:docs-cname",
     "deploy:docs": "gh-pages -d docs/build -m 'deploy docs [ci skip]'",
+    "postdeploy:docs": "yarn build:changelog && yarn deploy:changelog",
     "lint": "cross-env NODE_ENV=production eslint .",
     "lint:fix": "yarn lint --fix",
     "prettier": "prettier --list-different \"**/*.{js,jsx,ts,tsx}\"",