Update stac-js to fix basemaps radiantearth#629

Author: m-mohr

package-lock.json

@@ -55,7 +55,7 @@
     "ol-stac": "^1.0.0",
     "proj4": "^2.15.0",
     "remove-markdown": "^0.6.2",
-    "stac-js": "~0.1.5",
+    "stac-js": "~0.1.6",
     "stac-node-validator": "2.0.0-rc.1",
     "streamsaver-js": "^2.0.7",
     "urijs": "^1.19.11",