Merge branch '6.0-gt-actions-preparation' into 6.0

Author: alex-kulakov

Orm/Xtensive.Orm.Tests.Framework/Orm.config

@@ -104,9 +104,6 @@
     <domain name="mssql2019cs" provider="sqlserver"
             connectionString="Data Source=localhost\DO_SQL2019,1419;Initial Catalog=DO-Tests;User ID=dotest;Password=dotest;MultipleActiveResultSets=True;Encrypt=false" />
 
-    <domain name="mssql2019cs" provider="sqlserver"
-            connectionString="Data Source=localhost\DO_SQL2019,1419;Initial Catalog=DO-Tests;User ID=dotest;Password=dotest;MultipleActiveResultSets=True" />
-
     <domain name="pgsql83cs" provider="postgresql"
             connectionString="HOST=localhost;PORT=5483;DATABASE=dotest;USER ID=dotest;PASSWORD=dotest" />