fix: upgrade styled-components from 5.2.1 to 5.2.3

Snyk has created this PR to upgrade styled-components from 5.2.1 to 5.2.3.

See this package in npm:
https://www.npmjs.com/package/styled-components

See this project in Snyk:
https://app.snyk.io/org/wambugucoder/project/4ad982c5-88ce-4f1c-98fc-b63137218714?utm_source=github&utm_medium=upgrade-pr

Author: snyk-bot

client/package-lock.json

@@ -35,7 +35,7 @@
     "react-text-loop": "^2.3.0",
     "redux": "^4.0.5",
     "redux-thunk": "^2.3.0",
-    "styled-components": "^5.2.1"
+    "styled-components": "^5.2.3"
   },
   "scripts": {
     "start": "react-scripts start",