all: run goimports

gioui.org/ui was renamed from gioui.org/ui/ui before the release,
but the import order wasn't changed accordingly.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

ui/app/window.go

@@ -9,10 +9,10 @@ import (
 	"sync"
 	"time"
 
+	"gioui.org/ui"
 	"gioui.org/ui/app/internal/gpu"
 	"gioui.org/ui/key"
 	"gioui.org/ui/pointer"
-	"gioui.org/ui"
 )
 
 type WindowOptions struct {