WIP 6.0 major

[sl0thentr0py]

• Drop async configuration #1894
• Migrate from to_hash to to_h #2351

[github-actions]

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## Unreleased

- WIP 6.0 major ([#2352](https://github.com/getsentry/sentry-ruby/pull/2352))

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Generated by 🚫 dangerJS against 913c75e

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.98%. Comparing base (9446a30) to head (913c75e).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2352      +/-   ##
==========================================
- Coverage   98.16%   97.98%   -0.19%     
==========================================
  Files         126      126              
  Lines        4741     4714      -27     
==========================================
- Hits         4654     4619      -35     
- Misses         87       95       +8     

Components	Coverage Δ
sentry-ruby	98.48% <100.00%> (-0.04%)	⬇️
sentry-rails	96.57% <100.00%> (-0.49%)	⬇️
sentry-sidekiq	95.73% <ø> (-1.90%)	⬇️
sentry-resque	92.85% <ø> (ø)
sentry-delayed_job	95.65% <ø> (ø)
sentry-opentelemetry	99.31% <ø> (ø)

Files with missing lines	Coverage Δ
sentry-rails/lib/sentry/rails/active_job.rb	100.00% <100.00%> (ø)
sentry-ruby/lib/sentry/background_worker.rb	100.00% <100.00%> (ø)
sentry-ruby/lib/sentry/breadcrumb.rb	96.96% <100.00%> (ø)
sentry-ruby/lib/sentry/breadcrumb_buffer.rb	100.00% <100.00%> (ø)
sentry-ruby/lib/sentry/check_in_event.rb	100.00% <100.00%> (ø)
sentry-ruby/lib/sentry/client.rb	100.00% <100.00%> (ø)
sentry-ruby/lib/sentry/configuration.rb	98.86% <ø> (-0.03%)	⬇️
sentry-ruby/lib/sentry/cron/monitor_config.rb	95.45% <100.00%> (ø)
sentry-ruby/lib/sentry/cron/monitor_schedule.rb	100.00% <100.00%> (ø)
sentry-ruby/lib/sentry/error_event.rb	100.00% <100.00%> (ø)
... and 16 more

... and 6 files with indirect coverage changes