Data browser column headers are not fixed when scrolling

[mtrezza]

New Issue Checklist

• I am not disclosing a vulnerability.
• I am not just asking a question.
• I have searched through existing issues.
• I can reproduce the issue with the latest versions of Parse Server and Parse Dashboard.

Issue Description

When scrolling down in the data browser, the column headers move as well and disappear.

Steps to reproduce

1. Open data browser with sufficient number of rows to scroll down.
2. Scroll down.
3. Column headers disappear.

Expected Outcome

Column headers should stay visible at fixed position.

Environment

Dashboard

• Parse Dashboard version: 6.0.0

[parse-github-assistant]

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