Error during package import
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## Description of the issue
Error during package import

## Context information (for bug reports)

**Output of `bench version`**
```
Site on frappecloud
```

## Steps to reproduce the issue

1. Publish the package on the first site
2. Attach the package on the package import on the second site
3. Check "Activate" and "Save"

### Observed result
subprocess.CalledProcessError: Command '['tar', 'xzf', './bee-live.frappe.cloud/private/files/BeeEspRef-0.0.1.tar.gz', '-C', './bee-live.frappe.cloud/packages']' returned non-zero exit status 2.
### Expected result
success import
### Stacktrace / full error message

```
### App Versions
```
{
	"erpnext": "14.27.6",
	"frappe": "14.39.0",
	"hrms": "14.4.3",
	"payments": "0.0.1"
}
```
### Route
```
Form/Package Import/Package Import at 2023-06-21 11:41:47.665001
```
### Traceback
```
Traceback (most recent call last):
  File "apps/frappe/frappe/app.py", line 66, in application
    response = frappe.api.handle()
  File "apps/frappe/frappe/api.py", line 54, in handle
    return frappe.handler.handle()
  File "apps/frappe/frappe/handler.py", line 47, in handle
    data = execute_cmd(cmd)
  File "apps/frappe/frappe/handler.py", line 85, in execute_cmd
    return frappe.call(method, **frappe.form_dict)
  File "apps/frappe/frappe/__init__.py", line 1608, in call
    return fn(*args, **newargs)
  File "apps/frappe/frappe/desk/form/save.py", line 28, in savedocs
    doc.save()
  File "apps/frappe/frappe/model/document.py", line 305, in save
    return self._save(*args, **kwargs)
  File "apps/frappe/frappe/model/document.py", line 339, in _save
    self.run_before_save_methods()
  File "apps/frappe/frappe/model/document.py", line 1045, in run_before_save_methods
    self.run_method("validate")
  File "apps/frappe/frappe/model/document.py", line 914, in run_method
    out = Document.hook(fn)(self, *args, **kwargs)
  File "apps/frappe/frappe/model/document.py", line 1264, in composer
    return composed(self, method, *args, **kwargs)
  File "apps/frappe/frappe/model/document.py", line 1246, in runner
    add_to_return_value(self, fn(self, *args, **kwargs))
  File "apps/frappe/frappe/model/document.py", line 911, in fn
    return method_object(*args, **kwargs)
  File "apps/frappe/frappe/core/doctype/package_import/package_import.py", line 18, in validate
    self.import_package()
  File "apps/frappe/frappe/core/doctype/package_import/package_import.py", line 34, in import_package
    subprocess.check_output(
  File "/usr/lib/python3.10/subprocess.py", line 421, in check_output
    return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
  File "/usr/lib/python3.10/subprocess.py", line 526, in run
    raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['tar', 'xzf', './bee-live.frappe.cloud/private/files/bee_esp_ref-0.0.1.tar.gz', '-C', './bee-live.frappe.cloud/packages']' returned non-zero exit status 2.

```
### Request Data
```
{
	"type": "POST",
	"args": {
		"doc": "{\\"name\\":\\"Package Import at 2023-06-21 11:19:06.269268\\",\\"owner\\":\\"jiri.sir@xx.com\\",\\"creation\\":\\"2023-06-21 11:19:06.269268\\",\\"modified\\":\\"2023-06-21 11:20:51.497539\\",\\"modified_by\\":\\"jiri.sir@xx.com\\",\\"docstatus\\":0,\\"idx\\":0,\\"attach_package\\":\\"\\",\\"activate\\":1,\\"force\\":0,\\"doctype\\":\\"Package Import\\",\\"__last_sync_on\\":\\"2023-06-21T09:24:36.341Z\\",\\"__unsaved\\":1}",
		"action": "Save"
	},
	"btn": {
		"jQuery360035348907895378591": {
			"events": {
				"click": [
					{
						"type": "click",
						"origType": "click",
						"guid": 2381,
						"namespace": ""
					}
				]
			}
		}
	},
	"freeze": true,
	"headers": {},
	"error_handlers": {},
	"url": "/api/method/frappe.desk.form.save.savedocs"
}
```
### Response Data
```
{
	"exception": "subprocess.CalledProcessError: Command '['tar', 'xzf', './bee-live.frappe.cloud/private/files/bee_esp_ref-0.0.1.tar.gz', '-C', './bee-live.frappe.cloud/packages']' returned non-zero exit status 2."
}
```
```

## Additional information

OS version / distribution, `Frappe` install method, etc.

diff --git a/frappe/core/doctype/package_import/package_import.py b/frappe/core/doctype/package_import/package_import.py
index 4939b357b0..25288603e1 100644
--- a/frappe/core/doctype/package_import/package_import.py
+++ b/frappe/core/doctype/package_import/package_import.py
@@ -10,6 +10,7 @@ from frappe.desk.form.load import get_attachments
 from frappe.model.document import Document
 from frappe.model.sync import get_doc_files
 from frappe.modules.import_file import import_doc, import_file_by_path
+from frappe.utils import get_files_path
 
 
 class PackageImport(Document):
@@ -35,7 +36,7 @@ class PackageImport(Document):
 			[
 				"tar",
 				"xzf",
-				frappe.get_site_path(attachment.file_url.strip("/")),
+				get_files_path(attachment.file_name, is_private=attachment.is_private),
 				"-C",
 				frappe.get_site_path("packages"),
 			]
['frappe/core/doctype/package_import/package_import.py']