Fix memory leaks in Assembly classes

[Vovanni]

Description

Replaced ConcurrentBag with ConcurrentQueue in Assembly to fix memory leaks caused by thread-local storage in long-running threads.

Problem

ConcurrentBag maintains thread-local lists that aren't properly garbage collected after threads terminate, causing gradual memory growth in long-running applications.

Solution

Switched to ConcurrentQueue which doesn't use thread-local storage and provides more predictable memory behavior.

Changes

src/ReportGenerator.Core/Parser/Analysis/Assembly.cs:

• Changed collection type from ConcurrentBag<Class> to ConcurrentQueue<Class> for classes;
• Updated relevant Add operation to Enqueue pattern.