Feat: add Baidu AI Cloud as storage backends for Loki

[arcosx]

Hi all, I plan to add Baidu AI Cloud (one of the Chinese cloud vendors) as one of the storage backends for Loki. In China many users don't use cloud vendors like amazon and google cloud. Adding Baidu AI cloud as a backend storage will help more Chinese users to try Loki.

links:

• about Baidu AI Cloud https://intl.cloud.baidu.com/
• about Baidu AI Cloud Object Storage Service (BOS) https://intl.cloud.baidu.com/doc/BOS/s/xjwvyq5g7-en

[CLAassistant]

All committers have signed the CLA.

[stale]

Hi! This issue has been automatically marked as stale because it has not had any
activity in the past 30 days.

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[arcosx]

new at #5848