message: change default engine version in uplugin file
diff: "DocsURL": "https://cesium.com/learn/unreal/",
  "MarketplaceURL": "com.epicgames.launcher://ue/marketplace/content/87b0d05800a545d49bf858ef3458c4f7",
  "SupportURL": "https://community.cesium.com",
  - "EngineVersion": "4.26.0",
  + "EngineVersion": "4.27.0",
  "CanContainContent": true,
  "IsBetaVersion": false,
  "IsExperimentalVersion": false,
  