feat: Use same icons in page tree state indicators and Manage verisons

[fsbraun]

Description

This PR reuses the icons of the django CMS core (which are loaded anyways) for the "Manage Verions" admin view. This creates a more uniform look and feel.

Before (with djangocms-versioning icons):

After (with django-cms core icons):

Related resources: icons of django CMS core

• The rules for showing the icons are identical to those of #295 ensuring a consistent experience: Icon is shown if the workflow allows for the action. If the user cannot execute it is grayed out.
• All icons are now produced using the templates/djangocms_versioning/admin/icons/ templates (before some icons had a independent templates)
• Works django admin (i.e., without djangocms-admin-style) and djangocms-admin-style 3.2.1+ (https://github.com/django-cms/djangocms-admin-style/pull/477); earlier versions inject css poisoning icon usage

  Checklist

• [x] I have opened this pull request against master
• [x] I have added or modified the tests when changing logic
• [x] I have followed the conventional commits guidelines to add meaningful information into the changelog
• [x] I have read the contribution guidelines and I have joined #workgroup-pr-review on Slack to find a “pr review buddy” who is going to review my pull request.

[codecov[bot]]

Codecov Report

Merging #302 (c61f1e4) into master (3e6fb53) will not change coverage. The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #302   +/-   ##
=======================================
  Coverage   86.91%   86.91%           
=======================================
  Files          30       30           
  Lines        1743     1743           
  Branches      269      269           
=======================================
  Hits         1515     1515           
  Misses        173      173           
  Partials       55       55           

Impacted Files	Coverage Δ
djangocms_versioning/admin.py	88.76% <100.00%> (ø)

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