[FLINK-27926][Docs] Translating the Upgrading Applications and Flink versions page to Chinese

[billyrrr]

What is the purpose of the change

Translate upgrading.md into chinese FLINK-27926. The documentation is about upgrading existing flink cluster.

NOTE: wrong issue number attached in previous edit of the issue and commit message

Brief change log

• Duplicate upgrading.md from current master to content.zh
• Translate the documentation with automatic translation
• Manually inspect translation and calibrate with translation table

Verifying this change

This change added tests and can be verified as follows:

• Rebuild doc and visually inspect the new page

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): no
• The public API, i.e., is any changed class annotated with @Public(Evolving): no
• The serializers: no
• The runtime per-record code paths (performance sensitive): no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: no
• The S3 file system connector: no

Documentation

• Does this pull request introduce a new feature? no
• If yes, how is the feature documented? not applicable

[flinkbot]

CI report:

• 59948ed Azure: FAILURE

Bot commands

The @flinkbot bot supports the following commands:

• @flinkbot run azure re-run the last Azure build

[MartijnVisser]

@billyrrr Thanks for the PR. Can you please make sure that you're following the code contribution guide, specifically for commit naming conventions? https://flink.apache.org/contributing/code-style-and-quality-pull-requests.html#commit-naming-conventions

We can have a look if the commit message is as requested.

[MartijnVisser]

I've changed the commit message and rebased. LGTM.