Bump lodash from 4.17.19 to 4.17.21 in /docusaurus

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] <[email protected]>

Author: dependabot[bot]

docusaurus/package-lock.json

@@ -5630,9 +5630,9 @@ [email protected], lodash.uniq@^4.5.0:
   integrity sha1-0CJTc662Uq3BvILklFM5qEJ1R3M=
 
 lodash@^4.17.11, lodash@^4.17.13, lodash@^4.17.14, lodash@^4.17.15, lodash@^4.17.19, lodash@^4.17.5:
-  version "4.17.19"
-  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.19.tgz#e48ddedbe30b3321783c5b4301fbd353bc1e4a4b"
-  integrity sha512-JNvd8XER9GQX0v2qJgsaN/mzFCNA5BRe/j8JN9d+tWyGLSodKQHKFicdwNYzWwI3wjRnaKPsGj1XkBjx/F96DQ==
+  version "4.17.21"
+  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.21.tgz#679591c564c3bffaae8454cf0b3df370c3d6911c"
+  integrity sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg==
 
 loglevel@^1.6.8:
   version "1.6.8"