Refactor JSDoc comments and remove whitespace

Remove extra whitespace and clean up JSDoc comments.

Author: songyumeng

src/common/mapping/WebMapBase.js

@@ -500,17 +500,18 @@ export function createWebMapBaseExtending(SuperClass, { mapRepo }) {
       this._cacheCleanLayers = [];
       this.clean(false);
     }
-    
     /**
-     * @version 11.3.0
-     * @function WebMapBase.prototype.changeBaseLayer
-     * @description 切换底图
-     * @param {BaseLayerConfig} layer - 图层配置对象
-     * @typedef {Object} BaseLayerConfig
+    * @typedef {Object} BaseLayerConfig
      * @property {string} id - 唯一标识
      * @property {string} title - 显示名称
      * @property {Array<Object>} layers - 上图的图层
      * @property {Object} sources - 图层对应的source
+     */
+    /**
+     * @version 11.3.0
+     * @function WebMapBase.prototype.changeBaseLayer
+     * @description 切换底图
+     * @param {BaseLayerConfig} layer - 图层配置对象
      * @returns {Object} 当前底图信息
      */
     changeBaseLayer() {