Fixes #3685 - Automatically add labels for issues reopened after ML triage

[ksy36]

This will help with analytics to determine the false-positive rate of the model using our Elastic search data: how many issues ML bot closed per week/ how many were reopened / how many of those ended up being "valid" ( i.e. milestoned to needsdiagnosis/moved).

• bugbug-reopened label for issues that have been reopened after ML bot closed them;
• bugbug-valid to issues that have bugbug-reopened label AND has been moved to needsdiagnosis or moved milestone;

[ksy36]

The build tests are failing with these errors:

  if request is None:
>           builder = EnvironBuilder(*args, **kwargs)
E           TypeError: __init__() got an unexpected keyword argument 'as_tuple'

env/lib/python3.9/site-packages/werkzeug/test.py:1081: TypeError

This is probably because of the change in werkzeug:
https://stackoverflow.com/questions/71661851/typeerror-init-got-an-unexpected-keyword-argument-as-tuple

https://flask.palletsprojects.com/en/2.1.x/changes/#version-2-1-0
The test client’s as_tuple parameter is removed. Use response.request.environ instead.

I'll address this in a separate PR.

[ksy36]

r? @karlcow

[karlcow]

Thanks @ksy36

[ksy36]

Thanks!