drop Rails < 7.1 conditionals

lib/active_record/pg_extensions/transaction.rb

@@ -17,7 +17,7 @@ def #{kind}(local: false)
             @#{kind} = timeout
             # If we have set an explicit timeout, the transaction has state that must be materialized
             # separately from any other transaction, so it cannot be `restartable`
-            dirty! unless ::Rails.version < '7.1'
+            dirty!
             return unless materialized?
             connection.set(#{kind.inspect}, "\#{(timeout * 1000).to_i}ms", local: true)
           end

spec/spec_helper.rb

@@ -27,12 +27,7 @@ def executed_statements
     @executed_statements ||= []
   end
 
-  methods = if Rails.version < "7.1"
-              %w[execute exec_no_cache exec_cache]
-            else
-              %w[internal_execute exec_no_cache exec_cache]
-            end
-  methods.each do |method|
+  %w[internal_execute exec_no_cache exec_cache].each do |method|
     class_eval <<-RUBY, __FILE__, __LINE__ + 1
       def #{method}(statement, *, **)
         materialize_transactions # this still needs to get called, even if we skip actually executing
@@ -47,8 +42,7 @@ def #{method}(statement, *, **)
   # we can't actually generate a dummy one of these, so we just query the db with something
   # that won't return anything
   def empty_pg_result
-    conn = (::Rails.version < "7.1") ? @connection : @raw_connection
-    conn.async_exec("SELECT 0 WHERE FALSE")
+    @raw_connection.async_exec("SELECT 0 WHERE FALSE")
   end
 end
 ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.prepend(StatementCaptureConnection)