build(deps-dev): bump karma from 2.0.5 to 6.3.16

Bumps [karma](https://github.com/karma-runner/karma) from 2.0.5 to 6.3.16.
- [Release notes](https://github.com/karma-runner/karma/releases)
- [Changelog](https://github.com/karma-runner/karma/blob/master/CHANGELOG.md)
- [Commits](https://github.com/karma-runner/karma/compare/v2.0.5...v6.3.16)

---
updated-dependencies:
- dependency-name: karma
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -164,7 +164,7 @@
     "file-loader": "^1.1.11",
     "html-webpack-plugin": "^3.2.0",
     "inject-loader": "^4.0.1",
-    "karma": "^2.0.2",
+    "karma": "^6.3.16",
     "karma-chai": "^0.1.0",
     "karma-coverage": "^1.1.2",
     "karma-electron": "^6.0.0",

src/renderer/components/FlightgearMap.vue

@@ -185,7 +185,7 @@ You should have received a copy of the GNU General Public License along with FG
         loadingInstance: Object,
         groundnetLoaded: false,
         pavementLoaded: false,
-        url: 'http://xjsjc.kongjian.xin:4200/tile/{z}/{x}/{y}.png',
+        url: 'https://a.tile.openstreetmap.de/{z}/{x}/{y}.png',
         attribution: '<A href="https://github.com/Portree-Kid/flightgear-airports" target="_blank">Flightgear Airports ' + require('electron').remote.app.getVersion() +
         '</A> <A href="https://www.electronjs.org/" target="_blank">Electron</A> ' +
         ' <A href="https://element.eleme.io/#/en-US/" target="_blank">element.io</A> ' +