Fix no issue if project has no env

[quangpham7]

Description

Fix exporter expose no issue if project has no environment.

In Sentry there are a few projects which have no environment. sentry-prometheus-exporter didn't get sentry_open_issue_events metric for these project. So I added a MR to fix that.

[italux]

Hey @quangpham7, first of all, thanks for contributing! Could you please elaborate more about the issue and changes you're proposing here?

Also, I saw that there are several code format changes on files, could you please review the lint workflow and reformat your code according to the black params?

[quangpham7]

Thanks @italux .

[italux]

Thanks @italux .

@quangpham7 I have some projects without environments and I'm trying to reproduce the issue you've mention but I wasn't able to. Are you running the Sentry saas version or hosted? There some exception, if yes, could please paste here?

[italux]

@quangpham7 while testing your fix I face a new issue as we can see below. I still investigating, but I can't find the source yet

2021-10-18 19:28:05,763 - 88563 - ERROR - exporter - Exception on /metrics/ [GET]
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 2070, in wsgi_app
    response = self.full_dispatch_request()
  File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 1515, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 1513, in full_dispatch_request
    rv = self.dispatch_request()
  File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 1499, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)
  File "exporter.py", line 61, in sentry_exporter
    REGISTRY.register(SentryCollector(sentry, ORG_SLUG, get_metric_config(), PROJECTS_SLUG))
  File "/usr/local/lib/python3.7/site-packages/prometheus_client/registry.py", line 26, in register
    names = self._get_names(collector)
  File "/usr/local/lib/python3.7/site-packages/prometheus_client/registry.py", line 66, in _get_names
    for metric in desc_func():
  File "/Users/italo.santos/github/sentry-prometheus-exporter/helpers/prometheus.py", line 262, in collect
    events_24h += int(issue.get("count") or 0)
AttributeError: 'str' object has no attribute 'get'