roachtest: fix db-console/* roachtests

- Fixes a bug introduced in cockroachdb#135992 that resulted
 in db-console/cypress to fail due to connection
 timeoutes. That PR stopped the roachtest from
 starting up CRDB on the workload node, but the
 test was still using this node to run the seed
 queries.

 Now, the seed queries are ran on a CRDB node.

- Increases the timeout for db-console/mixed-version.
  This test has been seen to timeout when there are
  multiple version upgrades and downgrades. In
  cockroachdb#136080, the cypress tests are run 22 times and
  timed out due to the combination of upgrade and
  downgrade nodes and running the tests (each run
  takes around 2 minutes).

Fixes: cockroachdb#136063, cockroachdb#136080
Epic: none
Release note: none

pkg/cmd/roachtest/tests/db_console.go

@@ -203,7 +203,7 @@ func registerDbConsole(r registry.Registry) {
 		Suites:           registry.Suites(registry.Nightly),
 		Randomized:       false,
 		Run:              runDbConsoleCypressMixedVersions,
-		Timeout:          1 * time.Hour,
+		Timeout:          2 * time.Hour,
 	})
 	r.Add(registry.TestSpec{
 		Name:             "db-console/cypress",
@@ -227,7 +227,7 @@ func runDbConsoleCypress(ctx context.Context, t test.Test, c cluster.Cluster) {
 	c.Start(ctx, t.L(), option.DefaultStartOpts(), install.MakeClusterSettings(), c.CRDBNodes())
 
 	cypressTest := newDbConsoleCypressTest(t, c, "cypress/e2e/health-check/*.ts", seedQueries)
-	db, err := c.ConnE(ctx, t.L(), cypressTest.testCluster.WorkloadNode()[0])
+	db, err := c.ConnE(ctx, t.L(), cypressTest.testCluster.CRDBNodes()[0])
 	if err != nil {
 		t.Fatal(err)
 	}