add dialyzer and fix id

lib/workload_service/release.ex

@@ -6,12 +6,14 @@ defmodule WorkloadService.Release do
   @app :workload_service
 
   def migrate do
-    load_app()
-    init_event_store()
+    :ok = load_app()
+    :ok = init_event_store()
 
     for repo <- repos() do
       {:ok, _, _} = Ecto.Migrator.with_repo(repo, &Ecto.Migrator.run(&1, :up, all: true))
     end
+
+    :ok
   end
 
   def rollback(repo, version) do
@@ -24,9 +26,10 @@ defmodule WorkloadService.Release do
   end
 
   defp load_app do
-    Application.ensure_all_started(:ssl)
-    Application.ensure_all_started(:postgrex)
-    Application.ensure_loaded(@app)
+    {:ok, _} = Application.ensure_all_started(:ssl)
+    {:ok, _} = Application.ensure_all_started(:postgrex)
+    :ok = Application.ensure_loaded(@app)
+    :ok
   end
 
   def init_event_store do
@@ -34,4 +37,4 @@ defmodule WorkloadService.Release do
 
     :ok = EventStore.Tasks.Init.exec(config, [])
   end
-end
+end