Disable background worker when executing rake tasks

[st0012]

This fixes #1508

(I know disabling background worker by setting background_worker_threads = 0 looks hacky, but I don't want to introduce another config option for background toggling atm.)

[codecov-commenter]

Codecov Report

Merging #1509 (3406ed1) into master (157f958) will increase coverage by 0.52%.
The diff coverage is 92.10%.

@@            Coverage Diff             @@
##           master    #1509      +/-   ##
==========================================
+ Coverage   98.21%   98.74%   +0.52%     
==========================================
  Files         218      123      -95     
  Lines       10560     6761    -3799     
==========================================
- Hits        10372     6676    -3696     
+ Misses        188       85     -103     

Impacted Files	Coverage Δ
sentry-ruby/lib/sentry/rake.rb	52.94% <50.00%> (-1.61%)	⬇️
sentry-ruby/lib/sentry/hub.rb	100.00% <100.00%> (ø)
sentry-ruby/spec/sentry/hub_spec.rb	100.00% <100.00%> (ø)
...ven/lib/raven/breadcrumbs/active_support_logger.rb
sentry-raven/lib/raven/base.rb
...y-raven/spec/raven/processors/http_headers_spec.rb
sentry-raven/spec/raven/transports/http_spec.rb
sentry-raven/spec/raven/event_spec.rb
...try-raven/lib/raven/interfaces/single_exception.rb
sentry-raven/lib/raven/event.rb
... and 88 more

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[y-yagi]

@st0012 Thanks for your quick fix! But, unfortunately, this can't fix my issue.

Rake::Application#top_level calls before the initialization process of a Rails application. So if users configure Sentry inside an initializer(that mentioned in doc), Sentry.initialized? inside Rake::Application#top_level returns false always and not using Sentry.get_current_hub.with_background_worker_disabled.

[st0012]

@y-yagi I see. I now see that the Rails rake task's initialization order is like this:

Rails rake_tasks block
top_level
Sentry SDK initializer
inside the task

I'll dig into this more.

[st0012]

@y-yagi I've updated the fix. It should work for both vanilla rake and Rails rake tasks.

[y-yagi]

@st0012 Thanks! I confirmed this fixes my issue.

[st0012]

@y-yagi sorry for the trouble and thanks for helping me verify the fix 🙂

[y-yagi]

@st0012 No problem! Thanks for your quick fix ❤️

[st0012]

@y-yagi fyi it's been released in version 4.6.2