Bump enshrined/svg-sanitize from 0.20.0 to 0.21.0

Bumps [enshrined/svg-sanitize](https://github.com/darylldoyle/svg-sanitizer) from 0.20.0 to 0.21.0.
- [Commits](https://github.com/darylldoyle/svg-sanitizer/compare/0.20.0...0.21.0)

---
updated-dependencies:
- dependency-name: enshrined/svg-sanitize
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

composer.json

@@ -70,7 +70,7 @@
         "doctrine/orm": "^2.18.1",
         "doctrine/persistence": "^3.2",
         "egulias/email-validator": "^3.2.6",
-        "enshrined/svg-sanitize": "^0.20",
+        "enshrined/svg-sanitize": "^0.21",
         "friendsofsymfony/jsrouting-bundle": "^2.8",
         "friendsofsymfony/oauth-server-bundle": "dev-master#dc8ff343363cf794d30eb1a123610d186a43f162",
         "friendsofsymfony/rest-bundle": "^3.6",