chore(package.json): element-plus2.1.9版本bug回退2.1.8

Former-commit-id: f6d3e0d0d9836838cc6dd10555272910aab5f036

package.json

@@ -15,7 +15,7 @@
     "axios": "^0.24.0",
     "better-scroll": "^2.4.2",
     "echarts": "^5.2.2",
-    "element-plus": "^2.1.9",
+    "element-plus": "^2.1.8",
     "nprogress": "^0.2.0",
     "path-browserify": "^1.0.1",
     "path-to-regexp": "^6.2.0",