Draft: Fix PipelineNotificationWorker args do not serialized to JSON safely

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What does this MR do and why?

Fix #383183

... for the PipelineNotificationWorker part, namely this warning:

Job arguments to PipelineNotificationWorker must be native JSON types, but :ref_status is a Symbol.
See https://github.com/sidekiq/sidekiq/wiki/Best-Practices
To disable this error, add `Sidekiq.strict_args!(false)` to your initializer.

References

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This issue is common across many workers. See #383181 (closed).

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Before	After

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. On master branch, run bundle exec rspec spec/models/ci/pipeline_spec.rb:3970:4012 --format documentation to see the warning
2. Checkout this MR, run bundle exec rspec spec/models/ci/pipeline_spec.rb:3970:4012 --format documentation again to see the warning disapear

Related to #383183