add version for timekeeper

GitOrigin-RevId: ec3664df27823ae2ee63982070dcd0615de19e5b

services/web/package.json

@@ -158,7 +158,7 @@
     "sinon-as-promised": "^4.0.3",
     "sinon-chai": "^2.14.0",
     "sinon-mongoose": "^2.3.0",
-    "timekeeper": "",
+    "timekeeper": "^2.2.0",
     "translations-sharelatex": "git+https://github.com/sharelatex/translations-sharelatex.git#master",
     "webpack": "^4.39.0",
     "webpack-cli": "^3.3.6",