refactor: remove unused props from components and improve error handling in about page (#385)

src/pages/posts/[...slug].astro

@@ -1,6 +1,5 @@
 ---
 import path from 'node:path'
-import { getCollection } from 'astro:content'
 import License from '@components/misc/License.astro'
 import Markdown from '@components/misc/Markdown.astro'
 import I18nKey from '@i18n/i18nKey'