[BACKPORT 2.19.0][PLAT-9249] yba-installer upgrade workflow fails

Summary:
We fail the upgrade workflow with some invalid
memory address. This happens with some of the code to migrate
between ybdb and postgres. Since ybdb is not yet supported,
i'll remove the migrate workflow for now to fix this

Orignal diff: f63d708 / D25550

Test Plan: run yba-installer upgrade from 2.18 -> 2.19.0.0-b189 with diff applied

Reviewers: sanketh, dshubin

Reviewed By: dshubin

Subscribers: muthu, sanketh, yugaware

Differential Revision: https://phorge.dev.yugabyte.com/D26130

managed/yba-installer/cmd/upgrade.go

@@ -85,7 +85,7 @@ var upgradeCmd = &cobra.Command{
 
 		// Check if upgrading requires DB migration.
 
-		dbMigrateFlow := state.GetDbUpgradeWorkFlow()
+		/*dbMigrateFlow := state.GetDbUpgradeWorkFlow()
 
 		var newDbServiceName string
 		if dbMigrateFlow == ybactlstate.PgToYbdb {
@@ -101,6 +101,7 @@ var upgradeCmd = &cobra.Command{
 			state.Postgres.IsEnabled = true
 			state.Ybdb.IsEnabled = false
 		}
+		*/
 
 		for _, name := range serviceOrder {
 			log.Info("About to upgrade component " + name)
@@ -119,7 +120,7 @@ var upgradeCmd = &cobra.Command{
 		}
 
 		var statuses []common.Status
-		serviceOrder = append([]string{newDbServiceName}, serviceOrder...)
+		//serviceOrder = append([]string{newDbServiceName}, serviceOrder...)
 		for _, name := range serviceOrder {
 			service := services[name]
 			status, err := service.Status()