Which issue does this PR close?

Closes #6507.

Rationale for this change

Security Token Service (STS) allows you to grant time-limited access to data stored on Object Storage Service (OSS) by using temporary access credentials. After the temporary access credentials expire, they can no longer be used to access the data. This helps improve flexibility and timeliness of access control.

What changes are included in this PR?

• Add the field security_token in OSSConfig.
• Add the method security_token in OSSBuilder.
• Improve the documentation for the access_key_id and access_key_secret fields in OssConfig.

Are there any user-facing changes?

• Add the method security_token in OSSBuilder.