Removes unused files

src/web/app/common/pages/about/base.pug

-extends ../../../base
-
-block head
-	link(rel='stylesheet', href='/_/resources/common/pages/about/style.css')
-	script(src='/_/resources/common/pages/about/script.js', async, defer)
-
-block body
-	article
-		header
-			h1
-				block header
-		div.body
-			block content

src/web/app/common/pages/about/pages/staff.pug

-extends ../base
-
-block title
-	| スタッフ | Misskey
-
-block header
-	| スタッフ
-
-block content
-	div.members
-		div.member
-			p しゅいろ
-			p 統括、設計、グラフィックデザイン、プログラム
\ No newline at end of file