Add KLINE_INTERVAL_1SECOND constant to Binance API

[hanoglu]

Summary

This pull request adds the missing constant KLINE_INTERVAL_1SECOND to the Binance API.

Details

The Binance API currently lacks the KLINE_INTERVAL_1SECOND constant, which represents a one-second interval for Kline/Candlestick data. This addition is essential for users who require high-resolution data for their trading strategies or analysis.

Changes Made

• Added KLINE_INTERVAL_1SECOND constant to the Binance API constants file.

Testing

• Tested the addition by retrieving one-second interval Kline data using the new constant.

Please review and merge this pull request at your earliest convenience. Thank you!