Add retry mechanism for Azure VM update API concurrent request conflicts

[Copilot]

• Analyze the issue and codebase to understand the problem
• Identify all begin_update calls that need retry mechanism
• Add retry decorator to begin_update calls in the resize method
• Add retry decorator to begin_update calls in the attach_nics method
• Add retry decorator to begin_update calls in the remove_extra_nics method
• Remove test file as requested by reviewer
• Implementation complete and ready for final review

Summary

Added retry mechanism to handle Azure ResourceExistsError (Conflict) errors when concurrent requests are made to VM update APIs. Created helper methods with @retry decorator (5 tries, 2s delay, 1.5x backoff) for:

• Resize._update_vm_size() - VM resize operations
• NetworkInterface._update_vm_nics() - Network interface attach/remove operations

All changes follow existing codebase patterns and are minimal in scope.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>add retry mechanism when invoke azure api</issue_title>
<issue_description>Please refer below call stack to fix the issue

2026-01-14 05:23:30.899[7624][ERROR] lisa.case[verify_vm_hot_resize_decrease][lisa_0_55] case failed
Traceback (most recent call last):
  File "C:\app\lsg-lisa\lisa\lisa\testsuite.py", line 867, in __run_case
    _call_with_timeout(
  File "C:\app\lsg-lisa\lisa\lisa\testsuite.py", line 60, in _call_with_timeout
    func_timeout(
  File "C:\Python\Lib\site-packages\func_timeout\dafunc.py", line 108, in func_timeout
    raise_exception(exception)
  File "C:\Python\Lib\site-packages\func_timeout\py3_raise.py", line 7, in raise_exception
    raise exception[0] from None
  File "C:\app\lsg-lisa\lisa\lisa\testsuite.py", line 609, in wrapper
    func(*args, **parameters)
  File "C:\app\lsg-lisa\lisa\lisa\microsoft\testsuites\core\vm_resize.py", line 68, in verify_vm_hot_resize_decrease
    self._verify_vm_resize(
  File "C:\app\lsg-lisa\lisa\lisa\microsoft\testsuites\core\vm_resize.py", line 154, in _verify_vm_resize
    raise e
  File "C:\app\lsg-lisa\lisa\lisa\microsoft\testsuites\core\vm_resize.py", line 133, in _verify_vm_resize
    expected_vm_capability, origin_vm_size, final_vm_size = resize.resize(
                                                            ^^^^^^^^^^^^^^
  File "C:\app\lsg-lisa\lisa\lisa\sut_orchestrator\azure\features.py", line 2273, in resize
    lro_poller = compute_client.virtual_machines.begin_update(
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\site-packages\azure\core\tracing\decorator.py", line 119, in wrapper_use_tracer
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\site-packages\azure\mgmt\compute\v2023_09_01\operations\_operations.py", line 16862, in begin_update
    raw_result = self._update_initial(
                 ^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\site-packages\azure\mgmt\compute\v2023_09_01\operations\_operations.py", line 16704, in _update_initial
    map_error(status_code=response.status_code, response=response, error_map=error_map)
  File "C:\Python\Lib\site-packages\azure\core\exceptions.py", line 163, in map_error
    raise error
azure.core.exceptions.ResourceExistsError: (Conflict) The request failed due to conflict with a concurrent request. To resolve it, please refer to https://aka.ms/activitylog to get more details on the conflicting requests.
Code: Conflict
Message: The request failed due to conflict with a concurrent request. To resolve it, please refer to https://aka.ms/activitylog to get more details on the conflicting requests.

```</issue_description>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes add retry mechanism when invoke azure api #4215

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[LiliDeng]

@copilot remove ‎selftests/azure/test_retry_mechanism.py‎

[Copilot]

@copilot remove ‎selftests/azure/test_retry_mechanism.py‎

Removed in eb31abe