batches: unify column headers on editor screen

Created by: adeola-ak

Closes issue #30464 (closed)

Minor UI improvements to address Kelli & Rob's feedback of:

• Library header should be h4 and not capitalized
• Editor should have batch spec header
• Workspaces preview header should be h4
• All three should have single underline

Result

Questions Looking at my photo preview, you can see the underline under the Library and Batch specification headers are in line but that is not true for the Workspaces preview header, which is slightly pushed down. Workspaces preview has the following class: <h4 className={styles.header}>Workspaces preview</h4>

Which is loaded from this file:

I'm not very familiar on how to go about finding and editing these styles. Can someone tell me how I can fix the padding?

Alsooooo.. i'm not clear why stuff from my last pull request on a different branch that was already merged is showing up in this PR? :(