Solr 10 support

[thomascorthals]

The release of Solr 10 necessitated a re-evaluation of the workaround for SOLR-6853. It breaks for Solr 10. Removing the workaround breaks backward compatibility. Since all affected Solr versions are now EOL, and the next Solarium release will be a new major version, I took this opportunity to revert the workaround so an out-of-the-box Solarium 7 will work with an out-of-the-box Solr 10. You can still opt-in to the workaround if needed, this information was added to the docs in all relevant places.

Solr 10 no longer comes bundled with a Tika Server. I've added a Docker container for an external Tika Server to the workflow. A small adjustment to the integration test was necessary because it behaves slightly differently.

WT_PHPS is no longer supported by Solr 10. I've commented it out in the integration tests for now, pending the result of #1169.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.21%. Comparing base (fbaa327) to head (21bec23).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1176   +/-   ##
=======================================
  Coverage   98.21%   98.21%           
=======================================
  Files         404      404           
  Lines       10635    10647   +12     
=======================================
+ Hits        10445    10457   +12     
  Misses        190      190           

Flag	Coverage Δ
unittests	98.21% <100.00%> (+<0.01%)	⬆️

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[mkalkbrenner]

Thank you!