Bump lodash from 4.17.19 to 4.17.21

Bumps [lodash](/~https://github.com/lodash/lodash) from 4.17.19 to 4.17.21.
- [Release notes](/~https://github.com/lodash/lodash/releases)
- [Commits](lodash/lodash@4.17.19...4.17.21)

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

package.json

@@ -46,7 +46,7 @@
     "expect": "24.9.0",
     "gitbook-cli": "2.3.2",
     "jsdom": "15.2.1",
-    "lodash": "4.17.19",
+    "lodash": "4.17.21",
     "mkdirp": "0.5.1",
     "mocha": "6.2.2",
     "prop-types": "^15.7.2",

yarn.lock

@@ -4262,10 +4262,10 @@ lodash.without@~4.4.0:
   resolved "https://registry.yarnpkg.com/lodash.without/-/lodash.without-4.4.0.tgz#3cd4574a00b67bae373a94b748772640507b7aac"
   integrity sha1-PNRXSgC2e643OpS3SHcmQFB7eqw=
 
-lodash@4.17.19, lodash@^4.15.0, lodash@^4.17.13, lodash@^4.17.14, lodash@^4.17.15, lodash@^4.17.4:
-  version "4.17.19"
-  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.19.tgz#e48ddedbe30b3321783c5b4301fbd353bc1e4a4b"
-  integrity sha512-JNvd8XER9GQX0v2qJgsaN/mzFCNA5BRe/j8JN9d+tWyGLSodKQHKFicdwNYzWwI3wjRnaKPsGj1XkBjx/F96DQ==
+lodash@4.17.21, lodash@^4.15.0, lodash@^4.17.13, lodash@^4.17.14, lodash@^4.17.15, lodash@^4.17.4:
+  version "4.17.21"
+  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.21.tgz#679591c564c3bffaae8454cf0b3df370c3d6911c"
+  integrity sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg==
 
 lodash@4.17.4:
   version "4.17.4"