software/js-drone: fix unserializable position

Workaround for https://github.com/bellard/quickjs/issues/315 .

software/js-drone/buildout.hash.cfg

@@ -46,4 +46,4 @@ md5sum = 3bbb0f80b644d86784aab99b03e88c2f
 
 [worker]
 _update_hash_filename_ = drone-scripts/worker.js.jinja2
-md5sum = 2afbc5c18a453404f6c60e874f592577
+md5sum = f3ad1e74bdb977c9444713f14a2ea6fe

software/js-drone/drone-scripts/worker.js.jinja2

@@ -80,7 +80,15 @@ import { evalScript, fdopen, loadFile, open } from "std";
 {% if isADrone -%}
       getAltitudeAbs: getAltitude,
       getClimbRate: getClimbRate,
-      getCurrentPosition: getPosition,
+      getCurrentPosition: function () {
+        const position = getPosition();
+        return {
+          latitude: position.latitude,
+          longitude: position.longitude,
+          altitude: position.altitude,
+          timestamp: position.timestamp
+        };
+      },
       getInitialAltitude: getInitialAltitude,
       gpsIsOk: gpsIsOk,
       getMaxCommandFrequency: getMaxCommandFrequency,