set_transaction_name does not apply :task as a category

[kaylareopelle]

Description

The public API method set_transaction_name allows the user to optionally pass in a :category argument with the values of either :controller, :task, :middleware, or :uri. These values map to overarching categories for transactions.

We have a customer who tried to use this method with the :task category, but did not have their transactions successfully assigned as Non-Web/Background tasks.

A refactor to the method NewRelic::Agent::Transaction#set_overriding_transaction_name made it so it would not be possible for any transaction pre-categorized as a web transaction to be overridden to be a non-web transaction.

Expected Behavior

Users of the public API should be able to pass in the category: :task argument to set_transaction_name and have the transaction be re-categorized as a Non-Web or Background transaction. This change should not re-categorize the parent transaction (if there is one).

Internal Reference: GTSE-14114

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[kaylareopelle]

After running some tests, this behavior is inherently different from how the agent currently behaves, even though the agent is not behaving in the documented way. Due to the number of broken tests to implement this fix, I think this needs to be included as part of our next major version release.

[workato-integration]

https://issues.newrelic.com/browse/NEWRELIC-3449

[kaylareopelle]

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