[FLINK-30848][table-planner] Enable CatalogTableITCase#testAlterTable

[LadyForest]

What is the purpose of the change

Enable CatalogTableITCase#testAlterTable.

Brief change log

Remove @Ignore.

Verifying this change

This change is already covered by existing tests.

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:

• f8c8464 Azure: SUCCESS

Bot commands

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

[fsk119]

LGTM