Updated PostgreSqlInstallerFacts with latest version (13) of install scripts

Author: Vytautas Kasparavičius

tests/Hangfire.PostgreSql.Tests/PostgreSqlInstallerFacts.cs

@@ -20,7 +20,7 @@ public void InstallingSchemaUpdatesVersionAndShouldNotThrowAnException()
 					PostgreSqlObjectsInstaller.Install(connection, schemaName);
 
 					var lastVersion = connection.Query<int>(@"select version from """ + schemaName + @""".""schema""").Single();
-					Assert.Equal(12, lastVersion);
+					Assert.Equal(13, lastVersion);
 
 					connection.Execute($@"DROP SCHEMA ""{schemaName}"" CASCADE;");
 				});