Forerunner 920XT 英文测试版固件更新至 6.21

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更新日志

Changes made from version 6.20 to 6.21:

• Restored the version of the pool swim distance algorithm that was present in the 5.25 beta. This will improve distance accuracy for the users having problems with released software versions. We will continue to work on improving the pool swim algorithm in future betas.