MDEV-27134: Sporadic failure of DROP DATABASE test

Let us create and drop a separate database for getting rid of the
default database in the MDEV-22781 test.

mysql-test/main/cte_nonrecursive.result

@@ -1693,7 +1693,9 @@ disconnect con1;
 #
 # MDEV-22781: create view with CTE without default database
 #
-drop database test;
+create database db;
+use db;
+drop database db;
 create database db1;
 create table db1.t1 (a int);
 insert into db1.t1 values (3),(7),(1);
@@ -1723,7 +1725,6 @@ a
 drop view db1.v1;
 drop table db1.t1;
 drop database db1;
-create database test;
 use test;
 #
 # MDEV-24597: CTE with union used multiple times in query

mysql-test/main/cte_nonrecursive.test

@@ -1205,7 +1205,9 @@ DROP TABLE test.t;
 --echo # MDEV-22781: create view with CTE without default database
 --echo #
 
-drop database test;
+create database db;
+use db;
+drop database db;
 create database db1;
 create table db1.t1 (a int);
 insert into db1.t1 values (3),(7),(1);
@@ -1227,7 +1229,6 @@ drop view db1.v1;
 drop table db1.t1;
 drop database db1;
 
-create database test;
 use test;
 
 --echo #