Register cpp language for syntax highlighting in production (#191)

PrismLight only highlights explicitly registered languages. In dev
mode webpack skips tree-shaking so unregistered grammars still work,
but the production static export strips them out. This caused C++
code blocks to render as plain text in production.

Author: czepluch

src/components/Code.tsx

@@ -7,10 +7,12 @@ import {
 import bash from 'react-syntax-highlighter/dist/cjs/languages/prism/bash'
 import javascript from 'react-syntax-highlighter/dist/cjs/languages/prism/javascript'
 import json from 'react-syntax-highlighter/dist/cjs/languages/prism/json'
+import cpp from 'react-syntax-highlighter/dist/cjs/languages/prism/cpp'
 import solidity from 'react-syntax-highlighter/dist/cjs/languages/prism/solidity'
 import { getLanguageFromCodeProperties } from '@/utils'
 
 SyntaxHighlighter.registerLanguage('bash', bash)
+SyntaxHighlighter.registerLanguage('cpp', cpp)
 SyntaxHighlighter.registerLanguage('javascript', javascript)
 SyntaxHighlighter.registerLanguage('json', json)
 SyntaxHighlighter.registerLanguage('solidity', solidity)