revert selenium version for CI

package.json

@@ -110,7 +110,7 @@
     "rollup-plugin-node-resolve": "^3.0.0",
     "rollup-plugin-replace": "^1.1.1",
     "rollup-watch": "^4.0.0",
-    "selenium-server": "^3.4.0",
+    "selenium-server": "^2.53.1",
     "serialize-javascript": "^1.3.0",
     "typescript": "^2.3.4",
     "uglify-js": "^3.0.15",

yarn.lock

@@ -4340,9 +4340,9 @@ saucelabs@^1.3.0:
   dependencies:
     https-proxy-agent "^1.0.0"
 
-selenium-server@^3.4.0:
-  version "3.4.0"
-  resolved "https://registry.yarnpkg.com/selenium-server/-/selenium-server-3.4.0.tgz#f9303656d956c8d6c856e4942167e0dec97fa7a8"
+selenium-server@^2.53.1:
+  version "2.53.1"
+  resolved "https://registry.yarnpkg.com/selenium-server/-/selenium-server-2.53.1.tgz#d681528812f3c2e0531a6b7e613e23bb02cce8a6"
 
 "semver@2 || 3 || 4 || 5", semver@^5.3.0:
   version "5.3.0"