Add length validations to ZentaoTrackerData fields

What does this MR do and why?

Add length validations to ZentaoTrackerData fields

Add maximum length validations to the following ZentaoTrackerData attrs:

• url
• api_url
• zentao_product_xid
• api_token fields

Changelog: changed

References

• https://gitlab.com/gitlab-org/gitlab/-/issues/368465
• N.B there are currently 332 rows in the zentao_tracker_data table. I don't think we have data for Self-Managed.

How to set up and validate locally

1. Enable the ZenTao integration at the group level.
2. Attempt to save a record with long data.

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