chore: remove unused test PrettyPrint function

internal/test/testdata.go

@@ -3,7 +3,6 @@
 package test
 
 import (
-	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"net/http"
@@ -115,12 +114,6 @@ func SetupTestStorage(t *testing.T) string {
 	return storage
 }
 
-func PrettyPrint(t *testing.T, ob interface{}) string {
-	b, err := json.MarshalIndent(ob, "", "  ")
-	require.NoError(t, err)
-	return string(b)
-}
-
 func SetTestStorageDir(dir string) {
 	testStorageDir = dir
 }