public static String generateSecWebSocketAccept(String webSocketKey) {
        final String acceptSeed = webSocketKey + MAGIC_GUID;
        final byte[] sha1 = Hashing.sha1().hashBytes(acceptSeed.getBytes(StandardCharsets.US_ASCII)).asBytes();
        return Base64.getEncoder().encodeToString(sha1);
    }
Generates Sec-WebSocket-Accept using Sec-WebSocket-Key.

@see <a href="https://datatracker.ietf.org/doc/html/rfc6455#section-1.3">Opening Handshake</a>
core/src/main/java/com/linecorp/armeria/internal/common/websocket/WebSocketUtil.java