Complete consistent table header styling for AOs

[jenniferthibault]

Since we're inching closer to having the tags for AOs in place, these styling tweaks should help make the patterns line up closer to 1:1.

Pattern from data tables and attributes present

• Title is h1 class
• Underline under title is grey and meets the edge of the filter panel and edge of the screen
• Page title is the data set, without verbiage ("Receipts" instead of "Searching receipts")
• Table headers have a 2px border top that meets the edge of the filter panel and edge of the screen
• Vertical lines between columns extend into header area
• Line height of column headers is tighter (check that we're using the same classes)
• The first row has a white background instead of grey

Current status of AO tables

• (missing the attributes listed above)

[noahmanger]

Resolved by #2144