docs: updated Docusaurus + fix recurring error (#1244)

www/docs/src/components/Banner/Banner.js

@@ -1,13 +1,14 @@
 import React, { useEffect, useState } from "react"
+
 import CloseIcon from "../close-icon"
-import styles from "./banner.module.css"
-import clsx from "clsx"
-import useThemeContext from "@theme/hooks/useThemeContext"
 import ConfLogo from "../../../static/img/logo.svg"
+import clsx from "clsx"
+import styles from "./banner.module.css"
+import {useColorMode} from '@docusaurus/theme-common';
 
 const Banner = (props) => {
   const [isBannerVisible, setIsBannerVisible] = useState(true)
-  const { isDarkTheme } = useThemeContext()
+  const { isDarkTheme } = useColorMode()
 
   const handleDismissBanner = () => {
     setIsBannerVisible(false)