chore(demo): remove now useless speedometer

import AdbWsBackend from '@yume-chan/adb-backend-ws';

import AdbWebCredentialStore from '@yume-chan/adb-credential-web';

import { observer } from 'mobx-react-lite';

import { useCallback, useEffect, useMemo, useRef, useState } from 'react';

import { useCallback, useEffect, useMemo, useState } from 'react';

import { globalState } from '../state';

import { CommonStackTokens, Icons } from '../utils';

function _Connect(): JSX.Element | null {

    const [supported, setSupported] = useState(true);

    const [bytesIn, setBytesIn] = useState(0);

    const byteInAcc = useRef(0);

    useEffect(() => {

        const id = setInterval(() => {

            setBytesIn(byteInAcc.current);

            byteInAcc.current = 0;

        }, 1000);

        return () => {

            clearInterval(id);

        };

    }, []);

    const [selectedBackend, setSelectedBackend] = useState<AdbBackend | undefined>();

    const [connecting, setConnecting] = useState(false);

                    />

                )}

            {!!globalState.device && (<div>Transfer Rate: {bytesIn.toLocaleString()}B/s</div>)}

            <Dialog

                hidden={!connecting}

                dialogContentProps={{