V3 Rename row-contents blades

[lrljoe]

Renaming blades from row-contents to collapsing-columns to improve maintainability and help understanding of structure

All Submissions:

• [x] Have you followed the guidelines in our Contributing document?
• [x] Have you checked to ensure there aren't other open Pull Requests for the same update/change?

New Feature Submissions:

1. [x] Does your submission pass tests and did you add any new tests needed for your feature?
2. [x] Did you update all templates (if applicable)?
3. [x] Did you add the relevant documentation (if applicable)?
4. [x] Did you test locally to make sure your feature works as intended?

Changes to Core Features:

• [x] Have you added an explanation of what your changes do and why you'd like us to include them?
• [x] Have you written new tests for your core changes, as applicable?
• [x] Have you successfully ran tests with your changes locally?

[codecov[bot]]

Codecov Report

Merging #1519 (3972e89) into develop (03a19f0) will not change coverage. The diff coverage is n/a.

@@            Coverage Diff             @@
##             develop    #1519   +/-   ##
==========================================
  Coverage      88.55%   88.55%           
  Complexity      1256     1256           
==========================================
  Files             95       95           
  Lines           2980     2980           
==========================================
  Hits            2639     2639           
  Misses           341      341