Bug fixes

-fixing 3ds bug

Cleanup code base.

• Issue #3176795: Updated the patch for [Page Manager] on the fix of variants take entity label, not the variant title
• Issue #3176813: Fixed [Chaos Tool Suite (ctools)] issue by adding the patch for Entity Bundle Condition Plugin does not work in all situations

Issue #3125891 by u_tiwari: SearchBuilder::flattenKeys throws Array offset Notice in PHP 7.4
Issue #3100331 by manuel.adan, kbrodej: Do not create, update or remove read-only indexes
Issue #3144329 by lekes: Order by relevance although fulltext field is empty
Issue #3110970 by shaktik, r.spring, timotej-pl, kbrodej, imalabya, bonfil1, drewfranz, humbl_dev, rferguson, benjamincizej, abhijeet.kumar2107, FiNeX, fgm, kiamlaluno, ptt-homme: Remove the code deprecated in Drupal 9
Issue #3008751 by Renrhaf, andyg5000: Searching using a condition on status field

Search API Solr 4.1.x is the unified release that supports Drupal 8 and 9 and a wide range of Solr versions.

The big changes in 4.x compared to 3.x:

This is a significant release with update hooks to change the way changes since the last build are stored.
Please report any issues via the issue queue, and be sure to backup your site before you run the update hooks, in case of issues.