Changes

feat(cd/tidb-operator): add Tencent COS upload functionality to pipeline (#3757)

- Updated the tidb-operator.groovy to include Tencent COS upload steps
alongside existing Qiniu Cloud uploads.
- Introduced a new Python script (upload_tencent_cos.py) for handling
file uploads to Tencent COS.
- Added a README file detailing the usage and configuration for the
Tencent COS upload script.
- Environment variables for Tencent COS credentials are now required in
the pipeline.

After parallel uploading for a period of time, if there are no issues,
then submit a separate PR to remove the logic for uploading to Qiniu
Cloud.

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: wuhuizuo <wuhuizuo@126.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
 (commit: 0061b7e)