refactor(resource-adm): use new StudioPageHeader component in resourceadm

[mgunnerud]

Description

• Replace old <AppHeader /> in resource admin with new StudioPageHeader component
• Create utility function to get name of app from organization (app name in resourceadm is always <org>-resources)

Related Issue(s)

• Resourceadm: use new StudioPageHeader component in resourceadm #13697

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 94.41%. Comparing base (939464c) to head (27d1c0f).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #13699      +/-   ##
==========================================
- Coverage   94.41%   94.41%   -0.01%     
==========================================
  Files        1574     1576       +2     
  Lines       21276    21316      +40     
  Branches     2541     2546       +5     
==========================================
+ Hits        20088    20125      +37     
  Misses        943      943              
- Partials      245      248       +3     

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

[wrt95]

🥳