🔧 Remove hidden field from extra_options

[chrisjsewell]

I have a suspicion this was added due to a misunderstanding:

When a user creates a need like:

.. req:: Requirement A
   :hide:

It is stored on the need docutils node as node_need["hidden"] = True, BUT on the need data item as need["hide"] = True.
Indeed, as you can see in the changes, its value is never anything except ""

closes #1014

(related to #1122)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (e142d24) 85.83% compared to head (262e44b) 85.83%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1124      +/-   ##
==========================================
- Coverage   85.83%   85.83%   -0.01%     
==========================================
  Files          56       56              
  Lines        6508     6507       -1     
==========================================
- Hits         5586     5585       -1     
  Misses        922      922              

Flag	Coverage Δ
pytests	85.83% <ø> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.