ransack 3.1.0 on Ruby Gems

What's Changed

Add full link to issue about merging searches by @scarroll32 in #1305
Add acts-as-taggable-on and polymorphic searches to documentation by @scarroll32 in #1306 and #1312
Put contributor list last in documentation site by @scarroll32 in #1308
Allow Ransack to be used with Rails 7.1.0.alpha by @yahonda in #1309
Drop Ruby 2.6 support by @yahonda in #1311
Ransack search with ActsAsTaggableOn by @scarroll32 in
Fix predicate name in "Using Predicates" documentation page by @maxymczech in #1313

Full Changelog: v3.0.1...v3.1.0