chore: execute goimports to format the code (#7983)

* chore: execute goimports to format the code

Signed-off-by: promalert <promalert@outlook.com>

* goimports -w .

---------

Signed-off-by: promalert <promalert@outlook.com>
Co-authored-by: Chris Lu <chris.lu@gmail.com>

weed/util/mem/slot_pool_test.go

@@ -1,8 +1,9 @@
 package mem
 
 import (
-	"github.com/stretchr/testify/assert"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestAllocateFree(t *testing.T) {