chore(deps): update dependency parcel-bundler to ^1.12.3

Author: renovate-bot

package.json

@@ -15,7 +15,7 @@
     "sourcegraph:prepublish": "parcel build src/extension.ts"
   },
   "devDependencies": {
-    "parcel-bundler": "^1.10.0",
+    "parcel-bundler": "^1.12.3",
     "sourcegraph": "^20.1.0",
     "typescript": "^3.0.3"
   },