Fix deprication warning call columns with a table name!

Author: Anna

lib/active_record/connection_adapters/sqlserver_adapter.rb

@@ -311,7 +311,7 @@ def pk_and_sequence_for(table_name)
       end
 
       def primary_key(table_name)
-        identity_column(table_name).try(:name) || schema_cache.columns[table_name].detect(&:is_primary?).try(:name)
+        identity_column(table_name).try(:name) || schema_cache .columns(table_name).detect(&:is_primary?).try(:name)
       end
 
       # === SQLServer Specific (DB Reflection) ======================== #