Fix flaky test case in Go unit/type/list.go (#1449)

Currently, we use the list key 'l' in multiple test cases and they may interact with each other. So we fix it by using a dedicated key for each test case.

For failure logs can see: https://github.com/apache/incubator-kvrocks/actions/runs/5014908898/jobs/8991680649#step:12:104

tests/gocase/unit/type/list/list_test.go

@@ -168,8 +168,8 @@ func TestZipList(t *testing.T) {
 
 	t.Run("ziplist implementation: value encoding and backlink", func(t *testing.T) {
 		iterations := 100
-		key := "l"
 		for j := 0; j < iterations; j++ {
+			key := fmt.Sprintf("l1-%d", j)
 			require.NoError(t, rdb.Del(ctx, key).Err())
 			var lis []string
 			for i := 0; i < 200; i++ {
@@ -212,8 +212,8 @@ func TestZipList(t *testing.T) {
 	})
 
 	t.Run("ziplist implementation: encoding stress testing", func(t *testing.T) {
-		key := "l"
 		for j := 0; j < 200; j++ {
+			key := fmt.Sprintf("l2-%d", j)
 			require.NoError(t, rdb.Del(ctx, key).Err())
 			var lis []string
 			l := int(rand.Int63n(400))