local state: make test more robust

agent/local/state_test.go

@@ -1036,14 +1036,12 @@ func TestAgent_UpdateCheck_DiscardOutput(t *testing.T) {
 	if err := a.State.AddCheck(check, ""); err != nil {
 		t.Fatalf("bad: %s", err)
 	}
-
-	// wait until the check is in sync
-	retry.Run(t, func(r *retry.R) {
-		if inSync("web") {
-			return
-		}
-		r.FailNow()
-	})
+	if err := a.State.SyncFull(); err != nil {
+		t.Fatal("bad: %s", err)
+	}
+	if !inSync("web") {
+		t.Fatal("check should be in sync")
+	}
 
 	// update the check with the same status but different output
 	// and the check should still be in sync.