CI: bump gradle/actions/dependency-submission to v6.3.0

[tuhaihe]

The pinned v6.1.0 SHA is not in the ASF allowed-actions list, so the Dependency Submission job is blocked on every push to main. v6.3.0 is the only entry for this action without an expires_at, so it will not need another bump on a schedule.

https://github.com/apache/infrastructure-actions/blob/ec1b354a0455b41001d77473236d02a0ee0adba4/actions.yml#L575-L580

closes: #ISSUE_Number

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[tuhaihe]

Errors: https://github.com/apache/cloudberry-pxf/actions/workflows/dependency-submission.yml