logictest: fix user cmd to respect nodeidx for cockroach-go testserver

This patch fixes the client creation for logic tests that use the
cockroach-go testserver to use the specified nodeidx when connecting.

Release note: None

pkg/sql/logictest/logic.go

@@ -1169,8 +1169,9 @@ func (t *logicTest) setUser(user string, nodeIdx int) func() {
 	var cleanupFunc func()
 	pgUser = strings.TrimPrefix(user, "host-cluster-")
 	if t.cfg.UseCockroachGoTestserver {
-		pgURL = *t.testserverCluster.PGURL()
+		pgURL = *t.testserverCluster.PGURLForNode(nodeIdx)
 		pgURL.User = url.User(pgUser)
+		pgURL.Path = "test"
 		cleanupFunc = func() {}
 	} else {
 		addr = t.cluster.Server(nodeIdx).ServingSQLAddr()

pkg/sql/logictest/testdata/logic_test/testserver_upgrade_node

@@ -24,6 +24,29 @@ SELECT crdb_internal.node_executable_version()
 ----
 22.2
 
+# start of test that user cmd nodeidx opt works when used for a previously used user
+
+user root nodeidx=2
+
+query T
+SELECT crdb_internal.node_executable_version()
+----
+22.2
+
+query B
+SELECT crdb_internal.node_executable_version() SIMILAR TO '1000022.2-%'
+----
+false
+
+user root nodeidx=0
+
+query B
+SELECT crdb_internal.node_executable_version() SIMILAR TO '1000022.2-%'
+----
+true
+
+# end of test that user cmd nodeidx opt works when used for a previously used user
+
 upgrade 2
 
 query B