remove unused dep

Author: Rich-Harris

packages/kit/test/apps/dev-only/package.json

@@ -12,7 +12,6 @@
 	"devDependencies": {
 		"@sveltejs/kit": "workspace:^",
 		"cross-env": "^7.0.3",
-		"rimraf": "^4.0.0",
 		"svelte": "^3.55.1",
 		"svelte-check": "^3.0.2",
 		"typescript": "^4.9.4",