Solarium 5.0.2 is too old and has known issues. In order to get composer to upgrade solarium to a recent version a core patch or a workaround is required. Have a look at this Core issue and this Search API Solr issue.
By Gast (nicht überprüft), 6 Juni, 2020
Solarium Error:
Solarium 5.0.2 is too old and has known issues. In order to get composer to upgrade solarium to a recent version a core patch or a workaround is required. Have a look at this Core issue and this Search API Solr issue.