Bump karma-electron from 6.3.0 to 7.3.0

Bumps [karma-electron](https://github.com/twolfson/karma-electron) from 6.3.0 to 7.3.0.
- [Changelog](https://github.com/twolfson/karma-electron/blob/master/CHANGELOG.md)
- [Commits](twolfson/karma-electron@6.3.0...7.3.0)

---
updated-dependencies:
- dependency-name: karma-electron
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

package.json

@@ -63,7 +63,7 @@
     "jasmine-reporters": "^2.3.2",
     "js-yaml": "^4.1.0",
     "karma": "^6.3.4",
-    "karma-electron": "^6.3.0",
+    "karma-electron": "^7.3.0",
     "karma-jasmine": "^1.1.0",
     "karma-requirejs": "^1.1.0",
     "lodash.template": "^4.5.0",