Fix maps wms zoom limitation (#1915)

When using WMS to customize base tile maps in region map or coordinate maps, user aren’t able to get into higher zoom levels than opensearch maps service default maximum zoom level.

Issue Resolved:
opensearch-project/maps#19

Signed-off-by: Junqiu Lei <junqiu@amazon.com>

src/plugins/maps_legacy/public/map/base_maps_visualization.js

@@ -164,7 +164,8 @@ export function BaseMapsVisualizationProvider() {
 
       try {
         if (this._wmsConfigured()) {
-          if (WMS_MINZOOM > this._opensearchDashboardsMap.getMaxZoomLevel()) {
+          const currentMaxZoomLevel = this._opensearchDashboardsMap.getMaxZoomLevel();
+          if (WMS_MINZOOM < currentMaxZoomLevel || WMS_MAXZOOM > currentMaxZoomLevel) {
             this._opensearchDashboardsMap.setMinZoom(WMS_MINZOOM);
             this._opensearchDashboardsMap.setMaxZoom(WMS_MAXZOOM);
           }