RUBY-3789 disambiguate spec test names

[jamis]

The rest of this ticket was previously implemented as part of RUBY-3706.

[Copilot]

Pull request overview

Disambiguates client backpressure spec test names (read vs write aggregates) and makes small readability tweaks in transaction timeout handling.

Changes:

• Update backpressure spec YAML test descriptions to distinguish read vs write aggregate scenarios.
• Refactor with_transaction commit-time timeout handling for clearer control flow.
• Simplify make_timeout_error_from branching.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
spec/spec_tests/data/client_backpressure/backpressure-retry-max-attempts.yml	Renames aggregate retry tests to explicitly indicate read vs write semantics.
spec/spec_tests/data/client_backpressure/backpressure-retry-loop.yml	Renames aggregate retry-loop tests to explicitly indicate read vs write semantics.
lib/mongo/session.rb	Minor refactors around withTransaction timeout/raise paths; adds RuboCop suppression on the transaction loop.

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[Copilot]

# rubocop:disable Metrics/BlockLength without a corresponding rubocop:enable will disable this cop for the remainder of the file. Add a matching # rubocop:enable Metrics/BlockLength after the loop block (or use a disable/enable pair around the minimal span) so the suppression is scoped appropriately.