Use project numbers in billing budget filter (#3555)

* Fixed project level billing budget filter

* Moved project_numbers local to concat block

* Fixed with try block

* fix project replacement

* tfdoc

* fix test

---------

Co-authored-by: Ludovico Magnocavallo <ludomagno@google.com>

modules/billing-account/budgets.tf

@@ -98,8 +98,9 @@ resource "google_billing_budget" "default" {
     }
     projects = concat(
       [
-        for v in each.value.filter.projects :
-        lookup(local.ctx.project_ids, v, v)
+        for v in each.value.filter.projects : try(
+          try("projects/${local.ctx.project_numbers[v]}", v), v
+        )
       ],
       lookup(local.ctx.project_sets, "$project_sets:${each.key}", [])
     )