move swagger-ui-dist from dependencies to devDependencies

packages/typespec-vscode/package.json

@@ -273,12 +273,10 @@
     "rimraf": "~6.0.1",
     "rollup": "~4.31.0",
     "semver": "^7.6.3",
+    "swagger-ui-dist": "^5.18.2",
     "typescript": "~5.7.3",
     "vitest": "^3.0.5",
     "vscode-languageclient": "~9.0.1",
     "yaml": "~2.7.0"
-  },
-  "dependencies": {
-    "swagger-ui-dist": "^5.18.2"
   }
 }