Merge pull request #5742 from plotly/karma-firefox-launcher-2.1.1

bump karma-firefox-launcher v2.1.1

Author: archmoj

package-lock.json

@@ -158,7 +158,7 @@
     "karma": "^6.3.2",
     "karma-browserify": "^8.0.0",
     "karma-chrome-launcher": "^3.1.0",
-    "karma-firefox-launcher": "^1.3.0",
+    "karma-firefox-launcher": "^2.1.1",
     "karma-ie-launcher": "^1.0.0",
     "karma-jasmine": "^3.3.1",
     "karma-jasmine-spec-tags": "^1.3.0",