Switch to event-driven infrastructure and improve support for asynchronous questions

[cortadocodes]

Summary

This pull request:

• Makes the SDK fully event-driven by using a single topic to emit/consume events
• Majorly refactors the event handler to facilitate asynchronous event retrieval
• Adds the ability to get and replay events from a BigQuery store

Contents (#632)

IMPORTANT: There are 4 breaking changes.

New features

• 💥 BREAKING CHANGE: Use single topic per workspace #639
• Add get_events function for retrieving events asynchronously from BigQuery
• Add EventReplayer class to replay asynchronously-retrieved events
• Add Manifest.download method

Enhancements

• Get subscription project name from topic by default
• Improve asking of asynchronous questions via Child.ask
• Return download path from Dataset.download
• Include question UUID in delivery acknowledgement log message
• Improve handling of invalid events
• Add datetime and uuid attributes to all events

Fixes

• Await successful publishing of question messages
• Fix api_access_endpoint usage in mock_generate_signed_url

Operations

• Add test BigQuery dataset, cloud function, and IAM roles to terraform config
• Switch to reusable workflows where possible

Dependencies

• Add google-cloud-bigquery
• Upgrade coolname
• Add db-dtypes for converting bigquery rows to dataframes

Refactoring

• 💥 BREAKING CHANGE: Rename x.received_messages to x.received_events
• 💥 BREAKING CHANGE: Rename record_messages parameters to record_events
• 💥 BREAKING CHANGE: Update ChildEmulator to use event* instead of message*
• Factor out making minimal dictionary
• Factor out creating push subscription
• Factor out emitting question event in Service.ask
• Factor out event handlers and related logic from OrderedMessageHandler into new AbstractEventHandler
• Move validation module into octue.cloud.events subpackage
• Rename OrderedMessageHandler to GoogleCloudPubSubEventHandler
• Rename "message" to "event" in event handler classes
• Rename GooglePubSubHandler to GoogleCloudPubSubHandler

Chores

• Update licence year to 2024

Testing

• Simplify various tests

Upgrade instructions

• Update all services in your services network to this version of octue or later (0.53.0+)
• Replace any usages of the received_messages methods with received_events
• Replace any usages of the record_messages parameters with record_events
• Replace the word message with event in usages of ChildEmulator methods (apart from in the case of monitor_message)