chore(deps): bump @docusaurus/preset-classic (#21)

Author: dependabot[bot]

package.json

@@ -24,7 +24,7 @@
  "dependencies": {
  "@discord-message-components/react": "0.2.1",
  "@docusaurus/core": "2.0.0-beta.16",
- "@docusaurus/preset-classic": "2.0.0-beta.15",
+ "@docusaurus/preset-classic": "2.0.0-beta.16",
  "@easyops-cn/docusaurus-search-local": "0.21.4",
  "@matteusan/sentro": "0.1.20",
  "@mdx-js/react": "1.6.22",