Bump lodash from 4.17.15 to 4.17.20

Bumps [lodash](https://github.com/lodash/lodash) from 4.17.15 to 4.17.20.
- [Release notes](https://github.com/lodash/lodash/releases)
- [Commits](https://github.com/lodash/lodash/compare/4.17.15...4.17.20)

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

services/document-updater/package-lock.json

@@ -3752,9 +3752,9 @@
       }
     },
     "lodash": {
-      "version": "4.17.15",
-      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.15.tgz",
-      "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A=="
+      "version": "4.17.19",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.19.tgz",
+      "integrity": "sha512-JNvd8XER9GQX0v2qJgsaN/mzFCNA5BRe/j8JN9d+tWyGLSodKQHKFicdwNYzWwI3wjRnaKPsGj1XkBjx/F96DQ=="
     },
     "lodash.at": {
       "version": "4.6.0",

services/document-updater/package.json

@@ -22,7 +22,7 @@
     "body-parser": "^1.19.0",
     "bunyan": "~0.22.1",
     "express": "4.17.1",
-    "lodash": "^4.17.13",
+    "lodash": "^4.17.19",
     "logger-sharelatex": "^2.2.0",
     "metrics-sharelatex": "^2.6.2",
     "mongodb": "^3.6.0",