fix: remove helptext from som properties

[JamalAlabdullah]

Description

• Removed helpText for properties; preselectedOptionIndex, showValidations and sortOrder
• Added trest

Related Issue(s)

• Remove the help texts and icons for the properties that are converted to Legg+) design #14364

Verification

• Your code builds clean without any errors or warnings
• Manual testing done (required)
• Relevant automated test added (if you find this hard, leave it and we'll help out)

Documentation

• User documentation is updated with a separate linked PR in altinn-studio-docs. (if applicable)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.57%. Comparing base (9bfa321) to head (17257a8).
Report is 33 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #14369   +/-   ##
=======================================
  Coverage   95.57%   95.57%           
=======================================
  Files        1862     1862           
  Lines       24135    24141    +6     
  Branches     2785     2788    +3     
=======================================
+ Hits        23066    23072    +6     
  Misses        812      812           
  Partials      257      257           

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

[mlqn]

I created a PR that will handle all help texts here: #14420, so I think this PR can be closed. Feel free to re-open if that is an error.