Refactor and test fixes

[Zerpet]

This pull request refactors the handling of queue and exchange types in the RabbitMQ AMQP package, simplifying type usage and improving test reliability. The main changes include removing wrapper structs for queue and exchange types in favor of using plain type aliases, updating all related interfaces and methods, and refactoring tests to use better setup/teardown patterns and more idiomatic assertions.

Refactoring of queue and exchange type handling

• Removed the QueueType and ExchangeType wrapper structs and their associated .String() methods, replacing them with direct usage of the TQueueType and TExchangeType type aliases throughout the codebase. All interfaces, specifications, and related methods now use these aliases directly. [1] [2]
• Updated all queue and exchange specification structs and their methods to use the new type aliases, simplifying the code and removing unnecessary conversions. [1] [2] [3] [4] [5] [6] [7] [8]
• Changed how queue and exchange types are set in arguments maps, using direct string conversion from the type alias instead of calling .String(). [1] [2] [3] [4] [5]

Updates to queue and exchange classes

• Refactored the AmqpExchange and AmqpQueue classes to use the new type aliases for setting and getting types, simplifying their APIs and internal logic. [1] [2] [3]

Test improvements

• Refactored tests to remove unnecessary use of sync.WaitGroup, replacing it with BeforeEach and AfterEach hooks for setup and cleanup, and improved assertion style to use Expect(...).ToNot(HaveOccurred()) for error checks. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10]
• Improved import organization and removed unused imports in test files. [1] [2]

[Zerpet]

@Gsantomaggio I opened an intermediate PR because the refactoring and small test changes were already accumulating quite some code. I'm continuing with the topology recovery in a different branch.

[Gsantomaggio]

Ok with me, much better.

Added the breaking change due to TExchangeType and TQueueType, even though they are both strings.

btw we are still in 0.x so it is ok

Thank you