Feature: emulate Redis Stream PEL in TestRedisBroker to route messages to min_idle_time subscribers

[ApusBerliozi]

Description

This PR presents general concepts of PEL implementation. What I propose:

1 - PEL is an external feature. While the best option would be to make it a part of TestRedisBroker, it is very hard to implement due to existing architecture. So, PEL would be created as an external fixture and passed into the class

2 - PEL is a class, that contains self._entries (which is basically a dict, with which we can receive needed Entry via correlation_id), and methods to get an entry, remove an entry and add accordingly

3 - We work with PEL in FakeProducer, we add an Entry to PEL after msg is formed, and check whether or not PEL is emtpy before it

Related #2927

Type of change

Please delete options that are not relevant.

• Bug fix (a non-breaking change that resolves an issue)
• New feature (a non-breaking change that adds functionality)
• This change requires a documentation update

Checklist

• My code adheres to the style guidelines of this project (just lint shows no errors)
• I have conducted a self-review of my own code
• I have made the necessary changes to the documentation
• My changes do not generate any new warnings
• I have added tests to validate the effectiveness of my fix or the functionality of my new feature
• Both new and existing unit tests pass successfully on my local environment by running just test-coverage
• I have ensured that static analysis tests are passing by running just static-analysis
• I have included code examples to illustrate the modifications

[ApusBerliozi]

Hey @powersemmi!
Could you please take a look at this one?